fix relative comparisons of float

cli/go.mod

@@ -2,4 +2,4 @@ module neemek.com/anglais/cli
 
 go 1.25
 
-require github.com/alecthomas/kong v1.12.1
+require github.com/alecthomas/kong v1.15.0

cli/go.sum

@@ -4,7 +4,10 @@ github.com/alecthomas/kong v1.5.1 h1:9quB93P2aNGXf5C1kWNei85vjBgITNJQA4dSwJQGCOY
 github.com/alecthomas/kong v1.5.1/go.mod h1:p2vqieVMeTAnaC83txKtXe8FLke2X07aruPWXyMPQrU=
 github.com/alecthomas/kong v1.12.1 h1:iq6aMJDcFYP9uFrLdsiZQ2ZMmcshduyGv4Pek0MQPW0=
 github.com/alecthomas/kong v1.12.1/go.mod h1:p2vqieVMeTAnaC83txKtXe8FLke2X07aruPWXyMPQrU=
+github.com/alecthomas/kong v1.15.0 h1:BVJstKbpO73zKpmIu+m/aLRrNmWwxXPIGTNin9VmLVI=
+github.com/alecthomas/kong v1.15.0/go.mod h1:wrlbXem1CWqUV5Vbmss5ISYhsVPkBb1Yo7YKJghju2I=
 github.com/alecthomas/repr v0.4.0 h1:GhI2A8MACjfegCPVq9f1FLvIBS+DrQ2KQBFZP1iFzXc=
 github.com/alecthomas/repr v0.4.0/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
+github.com/alecthomas/repr v0.5.2 h1:SU73FTI9D1P5UNtvseffFSGmdNci/O6RsqzeXJtP0Qs=
 github.com/hexops/gotextdiff v1.0.3 h1:gitA9+qJrrTCsiCl7+kh75nPqQt1cx4ZkudSTLoUqJM=
 github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg=

cli/main.go

@@ -3,13 +3,14 @@ package main
 import (
 	"bufio"
 	"errors"
-	"github.com/alecthomas/kong"
 	"log"
-	"neemek.com/anglais/core"
 	"os"
 	"path"
 	"path/filepath"
 	"strings"
+
+	"github.com/alecthomas/kong"
+	"neemek.com/anglais/core"
 )
 
 type Context struct {
@@ -306,6 +307,8 @@ func (cmd *ReplCmd) Run(ctx *Context) error {
 		vm.SetChunk(c.Chunk)
 		for vm.Next() {
 		}
+
+		println(vm.Stack.Pop().DebugString())
 	}
 }
 

core/all_test.go

@@ -1,113 +1,73 @@
 package core
 
 import (
+	"math/big"
 	"testing"
 )
 
 type AllTestCase struct {
 	src           string
 	expectedStack []Value
+	expectedScope []map[string]Value
 }
 
 func GetAllTestCases() map[string]AllTestCase {
 	return map[string]AllTestCase{
 		"constant_number": {
 			"a := 1",
-			[]Value{
-				&VariableValue{
-					"a",
-					&NumberValue{1},
-					0,
-				},
+			[]Value{&IntegerValue{new(big.Int).SetInt64(1)}},
+			[]map[string]Value{
+				{"a": &IntegerValue{new(big.Int).SetInt64(1)}},
 			},
 		},
 		"func": {
-			"func sum(a: number, b: number) number {\n\treturn a + b\n}\n_ = sum(1, 2)",
-			[]Value{
-				&VariableValue{
-					"sum",
-					&FunctionValue{
-						Name: "sum",
-						Params: []FunctionParameter{
-							{
-								"a",
-								&NumberSignature{},
-							},
-							{
-								"b",
-								&NumberSignature{},
-							},
-						},
-						Chunk: &Chunk{
-							Bytecode: []Bytecode{
-								InstructionDescend,
-								InstructionGetLocal, 0,
-								InstructionGetLocal, 1,
-								InstructionAdd,
-								InstructionReturn,
-								InstructionAscend,
-							},
-							Constants: []Value{&StringValue{"a"}, &StringValue{"b"}},
-						},
-					},
-					0,
-				},
-			},
+			"fn sum(a: int, b: int) -> int {\n\treturn a + b\n}\nres := sum(1, 2)",
+			[]Value{&IntegerValue{new(big.Int).SetInt64(3)}},
+			[]map[string]Value{},
 		},
 		"list": {
-			"a := [1, 2]",
+			"a := [1.0, 2.0]\n{}",
+			[]Value{&NilValue{}},
+			[]map[string]Value{
+				{"a": &ListValue{
 					[]Value{
-				&VariableValue{
-					"a",
-					&ListValue{
-						[]Value{
-							&NumberValue{1},
-							&NumberValue{2},
-						},
-					},
-					0,
+						&FloatValue{1},
+						&FloatValue{2},
 					},
+				}},
 			},
 		},
 		"constant_list_concat": {
-			"a := [1, 2] + [3]",
+			"a := [1, 2] + [3]\n{}",
+			[]Value{&NilValue{}},
+			[]map[string]Value{
+				{"a": &ListValue{
 					[]Value{
-				&VariableValue{
-					"a",
-					&ListValue{
-						[]Value{
-							&NumberValue{1},
-							&NumberValue{2},
-							&NumberValue{3},
-						},
-					},
-					0,
+						&IntegerValue{big.NewInt(1)},
+						&IntegerValue{big.NewInt(2)},
+						&IntegerValue{big.NewInt(3)},
 					},
+				}},
 			},
 		},
 		"list_concat": {
-			"a := [1, 2]\nb := a + [3]",
+			"a := [1.0, 2.0]\nb := a + [3.0]\nnil",
+			[]Value{&NilValue{}},
+			[]map[string]Value{
+				{
+					"a": &ListValue{
 						[]Value{
-				&VariableValue{
-					"a",
-					&ListValue{
+							&FloatValue{1},
+							&FloatValue{2},
+						},
+					},
+					"b": &ListValue{
 						[]Value{
-							&NumberValue{1},
-							&NumberValue{2},
+							&FloatValue{1},
+							&FloatValue{2},
+							&FloatValue{3},
 						},
 					},
-					0,
-				},
-				&VariableValue{
-					"b",
-					&ListValue{
-						[]Value{
-							&NumberValue{1},
-							&NumberValue{2},
-							&NumberValue{3},
-						},
-					},
-					0,
 				},
 			},
 		},
@@ -159,7 +119,13 @@ func TestAll(t *testing.T) {
 			}
 
 			t.Log("Comparing stacks")
-			CompareStacks(t, tc.expectedStack, vm.stack)
+
+			CompareStacks(t, tc.expectedStack, vm.Stack)
+
+			// expected scope == nil => we don't care
+			if tc.expectedScope != nil {
+				CompareScope(t, tc.expectedScope, vm.scope)
+			}
 		})
 	}
 }

core/compiler.go

@@ -2,6 +2,7 @@ package core
 
 import (
 	"fmt"
+	"math/big"
 	"strings"
 )
 
@@ -17,6 +18,9 @@ type Compiler struct {
 	source   []rune
 	Warnings []CompilerError
 
+	// optimize Whether to attempt some optimization of the emitted bytecode
+	optimize bool
+
 	stack *Stack[LocalVariable]
 }
 
@@ -128,6 +132,7 @@ func NewCompiler(source []rune) *Compiler {
 		nil,
 		source,
 		[]CompilerError{},
+		false,
 		NewStack[LocalVariable](256),
 	}
 
@@ -168,10 +173,14 @@ func (c *Compiler) Compile(p *Program) error {
 		}
 	}
 
-	for _, s := range p.Block.statements {
+	for i, s := range p.Block.statements {
 		if err := c.compile(s); err != nil {
 			return err
 		}
+
+		if i != len(p.Block.statements)-1 {
+			c.add(InstructionPop)
+		}
 	}
 
 	c.fileStack.Pop()
@@ -191,16 +200,20 @@ func (c *Compiler) compile(tree Node) error {
 			tree.(*StringNode).value,
 		})
 
-	case NumberNodeType:
+	case FloatNodeType:
 		c.add(InstructionConstant)
-		c.addConstant(&NumberValue{tree.(*NumberNode).value})
+		c.addConstant(&FloatValue{tree.(*FloatNode).value})
+
+	case IntegerNodeType:
+		c.add(InstructionConstant)
+		c.addConstant(&IntegerValue{tree.(*IntegerNode).value})
 
 	case ListNodeType:
 		l := tree.(*ListNode)
 
 		if len(l.items) == 0 {
 			c.add(InstructionNewList)
-		} else if c.isTreeConstant(l) {
+		} else if c.optimize && c.isTreeConstant(l) {
 			v, err := c.compute(l)
 			if err != nil {
 				panic(err) // this shouldn't happen
@@ -229,7 +242,7 @@ func (c *Compiler) compile(tree Node) error {
 		}
 
 	case UnaryNodeType:
-		if c.isTreeConstant(tree.(*UnaryNode).value) {
+		if c.optimize && c.isTreeConstant(tree.(*UnaryNode).value) {
 			v, err := c.compute(tree)
 			if err != nil {
 				return err
@@ -243,9 +256,19 @@ func (c *Compiler) compile(tree Node) error {
 				return err
 			}
 
+			vt, err := c.deduceSignature(tree.(*UnaryNode).value)
+			if err != nil {
+				return err
+			}
+
 			switch tree.(*UnaryNode).UnaryOperation {
 			case UnaryNegate:
-				c.add(InstructionNegate)
+				if vt.Type() == TypeInteger {
+					c.add(InstructionNegateInt)
+				} else {
+					c.add(InstructionNegateFloat)
+				}
+
 			case UnaryNot:
 				c.add(InstructionNot)
 			}
@@ -262,12 +285,21 @@ func (c *Compiler) compile(tree Node) error {
 		c.add(InstructionNil)
 
 	case BlockNodeType:
+		if len(tree.(*BlockNode).statements) == 0 {
+			c.add(InstructionNil)
+			return nil
+		}
+
 		c.addDescend()
-		for _, n := range tree.(*BlockNode).statements {
+		for i, n := range tree.(*BlockNode).statements {
 			err := c.compile(n)
 			if err != nil {
 				return err
 			}
+
+			if i != len(tree.(*BlockNode).statements)-1 {
+				c.add(InstructionPop)
+			}
 		}
 		c.addAscend()
 
@@ -283,7 +315,7 @@ func (c *Compiler) compile(tree Node) error {
 			return c.error(fmt.Sprintf("conditional requires boolean; cannot use non-boolean type %s", sig), n.condition)
 		}
 
-		if c.isTreeConstant(n.condition) {
+		if c.optimize && c.isTreeConstant(n.condition) {
 			v, err := c.compute(n.condition)
 			if err != nil {
 				return err
@@ -321,13 +353,10 @@ func (c *Compiler) compile(tree Node) error {
 		}
 
 		// we store the position of the jump over the else code here
-		var jumpOverElse Pos
-		if n.otherwise != nil {
 		// this would jump over the else/otherwise block in the code
 		c.add(InstructionJump)
-			jumpOverElse = c.ip
+		jumpOverElse := c.ip
 		c.advance(2)
-		}
 
 		// put the u16 of where to jump if the condition was false
 		c.putU16(jumpByPos, uint16(c.ip-jumpByPos-2))
@@ -337,9 +366,12 @@ func (c *Compiler) compile(tree Node) error {
 			if err != nil {
 				return err
 			}
-			c.putU16(jumpOverElse, uint16(c.ip-jumpOverElse-2))
+		} else {
+			c.add(InstructionNil)
 		}
 
+		c.putU16(jumpOverElse, uint16(c.ip-jumpOverElse-2))
+
 	case LoopNodeType:
 		n := tree.(*LoopNode)
 
@@ -353,7 +385,7 @@ func (c *Compiler) compile(tree Node) error {
 		}
 
 		alwaysLoop := false
-		if c.isTreeConstant(n.condition) {
+		if c.optimize && c.isTreeConstant(n.condition) {
 			v, err := c.compute(n.condition)
 			if err != nil {
 				return err
@@ -368,6 +400,8 @@ func (c *Compiler) compile(tree Node) error {
 			}
 		}
 
+		c.add(InstructionNil)
+
 		conditionPos := c.ip
 		jumpValuePos := Pos(0)
 		if !alwaysLoop {
@@ -381,6 +415,8 @@ func (c *Compiler) compile(tree Node) error {
 			c.advance(2)
 		}
 
+		c.add(InstructionPop)
+
 		err = c.compile(n.do)
 		if err != nil {
 			return err
@@ -397,6 +433,26 @@ func (c *Compiler) compile(tree Node) error {
 	case AssignNodeType:
 		n := tree.(*AssignNode)
 
+		switch n.dest.Type() {
+		case ReferenceNodeType:
+			d := n.dest.(*ReferenceNode)
+
+			if d.name == "_" {
+				return c.compile(n.value)
+			}
+
+			if n.declare && c.isVarDeclaredHere(d.name) {
+				return c.error(fmt.Sprintf("%s is already declared in this scope", d.name), n)
+			}
+
+			if err := c.addSetVar(d.name, n.value, n.declare); err != nil {
+				return err
+			}
+		default:
+			return c.error(fmt.Sprintf("cannot assign to %s", n.dest.Type()), n.dest)
+		}
+
+		/*
 			if n.name == "_" {
 				// allow non-ish statements
 				err := c.compile(n.value)
@@ -414,9 +470,10 @@ func (c *Compiler) compile(tree Node) error {
 					return err
 				}
 			}
+		*/
 
-	case CallNodeType:
-		n := tree.(*CallNode)
+	case InvokeNodeType:
+		n := tree.(*InvokeNode)
 
 		s, err := c.deduceSignature(n.source)
 		if err != nil {
@@ -428,10 +485,6 @@ func (c *Compiler) compile(tree Node) error {
 			return c.error(fmt.Sprintf("cannot call non-function value of type %s", s), n)
 		}
 
-		if !n.keep && f.Out.Type() != TypeNil {
-			c.warn(fmt.Sprintf("shouldn't void result of function call (output is non-nil %s)", f.Out), n)
-		}
-
 		if len(n.args) != len(f.In) {
 			return c.error(fmt.Sprintf("wrong argument count: function of signature %s got %d, requires %d", f, len(n.args), len(f.In)), n)
 		}
@@ -463,7 +516,7 @@ func (c *Compiler) compile(tree Node) error {
 				return c.error(fmt.Sprintf("argument #%d does not have expected type signature: got %s, requires %s", i, sig, f.In[i]), arg)
 			}
 
-			if c.isTreeConstant(arg) {
+			if c.optimize && c.isTreeConstant(arg) {
 				v, err := c.compute(arg)
 				if err != nil {
 					return err
@@ -486,10 +539,6 @@ func (c *Compiler) compile(tree Node) error {
 
 		c.add(InstructionCall)
 
-		if !n.keep {
-			c.add(InstructionPop)
-		}
-
 	case FunctionNodeType:
 		n := tree.(*FunctionNode)
 
@@ -538,6 +587,7 @@ func (c *Compiler) compile(tree Node) error {
 			n.yield,
 			c.Chunk,
 			nil,
+			nil,
 		}
 
 		// restore old chunk and ip
@@ -573,7 +623,7 @@ func (c *Compiler) compile(tree Node) error {
 }
 
 func (c *Compiler) compileBinary(binary *BinaryNode) error {
-	if c.isTreeConstant(binary) {
+	if c.optimize && c.isTreeConstant(binary) {
 		v, err := c.compute(binary)
 		if err != nil {
 			return err
@@ -593,38 +643,77 @@ func (c *Compiler) compileBinary(binary *BinaryNode) error {
 		return err
 	}
 
-	switch binary.BinaryOperation {
-	case BinaryAddition:
 	res, err := c.deduceSignature(binary)
 	if err != nil {
 		return err
 	}
 
+	inType, err := c.deduceSignature(binary.Left) // type(left) == type(right) because res is valid
+	if err != nil {
+		return err
+	}
+
+	switch binary.BinaryOperation {
+	case BinaryAddition:
 		if res.Type() == TypeString {
 			c.add(InstructionStringConcatenation)
 		} else if res.Type() == TypeList {
 			c.add(InstructionConcatLists)
+		} else if res.Type() == TypeFloat {
+			c.add(InstructionAddFloat)
+		} else if res.Type() == TypeInteger {
+			c.add(InstructionAddInt)
 		} else {
-			c.add(InstructionAdd)
+			return c.error("unimplemented binary compilation", binary)
 		}
 	case BinarySubtraction:
-		c.add(InstructionSub)
+		if res.Type() == TypeFloat {
+			c.add(InstructionSubFloat)
+		} else {
+			c.add(InstructionSubInt)
+		}
 	case BinaryMultiplication:
-		c.add(InstructionMul)
+		if res.Type() == TypeFloat {
+			c.add(InstructionMulFloat)
+		} else {
+			c.add(InstructionMulInt)
+		}
 	case BinaryDivision:
-		c.add(InstructionDiv)
+		if res.Type() == TypeFloat {
+			c.add(InstructionDivFloat)
+		} else {
+			c.add(InstructionDivInt)
+		}
 	case BinaryEquality:
 		c.add(InstructionEquals)
 	case BinaryInequality:
 		c.add(InstructionNotEqual)
+
 	case BinaryLess:
-		c.add(InstructionLess)
+		if inType.Type() == TypeFloat {
+			c.add(InstructionLessFloat)
+		} else {
+			c.add(InstructionLessInt)
+		}
 	case BinaryGreater:
-		c.add(InstructionGreater)
+		if inType.Type() == TypeFloat {
+			c.add(InstructionGreaterFloat)
+		} else {
+			c.add(InstructionGreaterInt)
+		}
 	case BinaryLessEqual:
-		c.add(InstructionLessOrEqual)
+		if inType.Type() == TypeFloat {
+			c.add(InstructionLessOrEqualFloat)
+		} else {
+			c.add(InstructionLessOrEqualInt)
+		}
 	case BinaryGreaterEqual:
-		c.add(InstructionGreaterOrEqual)
+		if inType.Type() == TypeFloat {
+			c.add(InstructionGreaterOrEqualFloat)
+		} else {
+			c.add(InstructionGreaterOrEqualInt)
+		}
+
 	case BinaryAnd:
 		c.add(InstructionAnd)
 	case BinaryOr:
@@ -638,8 +727,10 @@ func (c *Compiler) deduceSignature(tree Node) (TypeSignature, error) {
 	switch tree.Type() {
 	case StringNodeType:
 		return &StringSignature{}, nil
-	case NumberNodeType:
-		return &NumberSignature{}, nil
+	case FloatNodeType:
+		return &FloatSignature{}, nil
+	case IntegerNodeType:
+		return &IntegerSignature{}, nil
 	case ReferenceNodeType:
 		n := tree.(*ReferenceNode)
 		sig, err := c.getVarSignature(n.name, n)
@@ -695,17 +786,23 @@ func (c *Compiler) deduceSignature(tree Node) (TypeSignature, error) {
 
 		switch n.BinaryOperation {
 		case BinarySubtraction, BinaryMultiplication, BinaryDivision:
-			if l.Type() != TypeNumber {
-				return nil, c.error(fmt.Sprintf("cannot %s values of non-number type %s", n.BinaryOperation, l), n)
+			if l.Type() == TypeInteger {
+				return &IntegerSignature{}, nil
 			}
 
-			return &NumberSignature{}, nil
+			if l.Type() == TypeFloat {
+				return &FloatSignature{}, nil
+			}
+
+			return nil, c.error(fmt.Sprintf("cannot %s values of non-number type %s", n.BinaryOperation, l), n)
 		case BinaryAddition:
 			switch l.Type() {
 			case TypeString:
 				return &StringSignature{}, nil
-			case TypeNumber:
-				return &NumberSignature{}, nil
+			case TypeInteger:
+				return &IntegerSignature{}, nil
+			case TypeFloat:
+				return &FloatSignature{}, nil
 			case TypeList:
 				return &ListSignature{
 					l.(*ListSignature).Contents,
@@ -722,7 +819,7 @@ func (c *Compiler) deduceSignature(tree Node) (TypeSignature, error) {
 		case BinaryEquality, BinaryInequality:
 			return &BooleanSignature{}, nil
 		case BinaryLess, BinaryGreater, BinaryLessEqual, BinaryGreaterEqual:
-			if l.Type() != TypeNumber {
+			if l.Type() != TypeInteger && l.Type() != TypeFloat {
 				return nil, c.error(fmt.Sprintf("cannot perform number comparison (%s) on non-number type %s", n.BinaryOperation, l), n)
 			}
 
@@ -768,8 +865,8 @@ func (c *Compiler) deduceSignature(tree Node) (TypeSignature, error) {
 			return nil, c.error(fmt.Sprintf("cannot access property from value of type %s", sig), n)
 		}
 
-	case CallNodeType:
-		n := tree.(*CallNode)
+	case InvokeNodeType:
+		n := tree.(*InvokeNode)
 		sig, err := c.deduceSignature(n.source)
 		if err != nil {
 			return nil, err
@@ -852,10 +949,13 @@ func (c *Compiler) deduceSignature(tree Node) (TypeSignature, error) {
 
 		switch n.UnaryOperation {
 		case UnaryNegate:
-			if sig.Type() != TypeNumber {
-				return nil, c.error(fmt.Sprintf("cannot perform negation on type %s (must be number)", n.UnaryOperation), n)
+			if sig.Type() == TypeFloat {
+				return &FloatSignature{}, nil
+			} else if sig.Type() == TypeInteger {
+				return &IntegerSignature{}, nil
 			}
-			return &NumberSignature{}, nil
+
+			return nil, c.error(fmt.Sprintf("cannot perform negation on type %s (must be number)", n.UnaryOperation), n)
 		case UnaryNot:
 			if sig.Type() != TypeBoolean {
 				return nil, c.error(fmt.Sprintf("cannot perform negation on type %s (must be boolean)", n.UnaryOperation), n)
@@ -864,6 +964,15 @@ func (c *Compiler) deduceSignature(tree Node) (TypeSignature, error) {
 		}
 
 		return nil, c.error(fmt.Sprintf("unimplemented result type deduction for unary %s", n.UnaryOperation), n)
+	case BlockNodeType:
+		n := tree.(*BlockNode)
+		if len(n.statements) == 0 {
+			return &NilSignature{}, nil
+		}
+
+		return c.deduceSignature(n.statements[len(n.statements)-1])
+	case AssignNodeType:
+		return c.deduceSignature(tree.(*AssignNode).value)
 	default:
 		return nil, c.error(fmt.Sprintf("impossible to deduce signature of %s", tree.Type()), tree)
 	}
@@ -929,8 +1038,12 @@ func (c *Compiler) affirmReturnSignature(tree Node, sig TypeSignature) error {
 	case AssignNodeType:
 		n := tree.(*AssignNode)
 
+		switch n.dest.Type() {
+		case ReferenceNodeType:
+			name := n.dest.(*ReferenceNode).name
+
 			if !n.declare {
-			prev, err := c.getVarSignature(n.name, n)
+				prev, err := c.getVarSignature(name, n)
 				if err != nil {
 					return err
 				}
@@ -941,7 +1054,7 @@ func (c *Compiler) affirmReturnSignature(tree Node, sig TypeSignature) error {
 				}
 
 				if !sig.Matches(prev) {
-				return c.error(fmt.Sprintf("cannot assign value of type %s to variable %s of type %s", sig, n.name, prev), n.value)
+					return c.error(fmt.Sprintf("cannot assign value of type %s to variable %s of type %s", sig, name, prev), n.value)
 				}
 
 				return nil
@@ -951,7 +1064,11 @@ func (c *Compiler) affirmReturnSignature(tree Node, sig TypeSignature) error {
 			if err != nil {
 				return err
 			}
-		c.registerVar(n.name, sig)
+			c.registerVar(name, sig)
+		default:
+			return c.error("can neither assign nor declare to", n.dest)
+		}
+
 	default:
 	}
 
@@ -1040,7 +1157,7 @@ func (c *Compiler) isLocal(name string) bool {
 // isTreeConstant check if a node tree is constant (predictable)
 func (c *Compiler) isTreeConstant(tree Node) bool {
 	switch tree.Type() {
-	case StringNodeType, NumberNodeType, BooleanNodeType, NilNodeType:
+	case StringNodeType, FloatNodeType, IntegerNodeType, BooleanNodeType, NilNodeType:
 		return true
 	case ListNodeType:
 		for _, item := range tree.(*ListNode).items {
@@ -1054,13 +1171,13 @@ func (c *Compiler) isTreeConstant(tree Node) bool {
 		return c.isTreeConstant(tree.(*UnaryNode).value)
 	case BinaryNodeType:
 		return c.isTreeConstant(tree.(*BinaryNode).Left) && c.isTreeConstant(tree.(*BinaryNode).Right)
-	case CallNodeType:
-		for _, arg := range tree.(*CallNode).args {
+	case InvokeNodeType:
+		for _, arg := range tree.(*InvokeNode).args {
 			if !c.isTreeConstant(arg) {
 				return false
 			}
 		}
-		return c.isTreeConstant(tree.(*CallNode).source)
+		return c.isTreeConstant(tree.(*InvokeNode).source)
 	case BlockNodeType, ConditionalNodeType, LoopNodeType, AssignNodeType, FunctionNodeType,
 		ReturnNodeType, AccessNodeType, BreakpointNodeType, ReferenceNodeType:
 		return false
@@ -1076,8 +1193,13 @@ func (c *Compiler) compute(tree Node) (Value, error) {
 			n.value,
 		}, nil
 
-	case *NumberNode:
-		return &NumberValue{
+	case *FloatNode:
+		return &FloatValue{
+			n.value,
+		}, nil
+
+	case *IntegerNode:
+		return &IntegerValue{
 			n.value,
 		}, nil
 
@@ -1114,13 +1236,17 @@ func (c *Compiler) compute(tree Node) (Value, error) {
 
 		switch n.UnaryOperation {
 		case UnaryNegate:
-			if v.Type() != NumberValueType {
-				return nil, c.error(fmt.Sprintf("cannot negate %s value (not a number)", v.Type()), n)
+			if v.Type() == FloatValueType {
+				return &FloatValue{
+					-v.(*FloatValue).Number,
+				}, nil
+			} else if v.Type() == IntegerValueType {
+				return &IntegerValue{
+					new(big.Int).Neg(v.(*IntegerValue).Number),
+				}, nil
 			}
 
-			return &NumberValue{
-				-v.(*NumberValue).Number,
-			}, nil
+			return nil, c.error(fmt.Sprintf("cannot negate %s value (not a number)", v.Type()), n)
 		case UnaryNot:
 			if v.Type() != BoolValueType {
 				return nil, c.error(fmt.Sprintf("cannot invert %s value (not a boolean)", v.Type()), n)
@@ -1133,7 +1259,7 @@ func (c *Compiler) compute(tree Node) (Value, error) {
 
 		return nil, c.error(fmt.Sprintf("unimplemented unary %s", v.Type()), n)
 
-	case *CallNode:
+	case *InvokeNode:
 		source, err := c.compute(n.source)
 		if err != nil {
 			return nil, err
@@ -1180,7 +1306,7 @@ func (c *Compiler) computeBinary(n *BinaryNode) (Value, error) {
 	// perform type check
 	switch n.BinaryOperation {
 	case BinarySubtraction, BinaryMultiplication, BinaryDivision, BinaryLess, BinaryGreater, BinaryLessEqual, BinaryGreaterEqual:
-		if l.Type() != NumberValueType {
+		if l.Type() != FloatValueType && l.Type() != IntegerValueType {
 			return nil, c.error(fmt.Sprintf("cannot %s values of non-number type %s", n.BinaryOperation, l.Type()), n)
 		}
 	case BinaryAnd, BinaryOr:
@@ -1196,37 +1322,67 @@ func (c *Compiler) computeBinary(n *BinaryNode) (Value, error) {
 	switch n.BinaryOperation {
 	case BinaryAddition:
 		switch l.Type() {
-		case NumberValueType:
-			v = l.(*NumberValue).Number + r.(*NumberValue).Number
+		case FloatValueType:
+			v = l.(*FloatValue).Number + r.(*FloatValue).Number
 		case StringValueType:
 			v = l.(*StringValue).Text + r.(*StringValue).Text
 		case ListValueType:
 			v = append(l.(*ListValue).Items, r.(*ListValue).Items...)
+		case IntegerValueType:
+			v = new(big.Int).Add(l.(*IntegerValue).Number, r.(*IntegerValue).Number)
 		default:
 			return nil, c.error(fmt.Sprintf("cannot add values of type %s", l.Type()), n)
 		}
 	case BinarySubtraction:
-		v = l.(*NumberValue).Number - r.(*NumberValue).Number
+		if l.Type() == FloatValueType {
+			v = l.(*FloatValue).Number - r.(*FloatValue).Number
+		} else {
+			v = new(big.Int).Sub(l.(*IntegerValue).Number, r.(*IntegerValue).Number)
+		}
 	case BinaryMultiplication:
-		v = l.(*NumberValue).Number * r.(*NumberValue).Number
+		if l.Type() == FloatValueType {
+			v = l.(*FloatValue).Number * r.(*FloatValue).Number
+		} else {
+			v = new(big.Int).Mul(l.(*IntegerValue).Number, r.(*IntegerValue).Number)
+		}
 	case BinaryDivision:
-		v = l.(*NumberValue).Number / r.(*NumberValue).Number
+		if l.Type() == FloatValueType {
+			v = l.(*FloatValue).Number / r.(*FloatValue).Number
+		} else {
+			v = new(big.Int).Div(l.(*IntegerValue).Number, r.(*IntegerValue).Number)
+		}
 	case BinaryAnd:
 		v = l.(*BoolValue).Boolean && r.(*BoolValue).Boolean
 	case BinaryOr:
-		v = l.(*BoolValue).Boolean && r.(*BoolValue).Boolean
+		v = l.(*BoolValue).Boolean || r.(*BoolValue).Boolean
 	case BinaryEquality:
 		v = l.Equals(r)
 	case BinaryInequality:
 		v = !l.Equals(r)
 	case BinaryLess:
-		v = l.(*NumberValue).Number < r.(*NumberValue).Number
+		if l.Type() == FloatValueType {
+			v = l.(*FloatValue).Number < r.(*FloatValue).Number
+		} else {
+			v = l.(*IntegerValue).Number.Cmp(r.(*IntegerValue).Number) == -1
+		}
 	case BinaryGreater:
-		v = l.(*NumberValue).Number > r.(*NumberValue).Number
+		if l.Type() == FloatValueType {
+			v = l.(*FloatValue).Number > r.(*FloatValue).Number
+		} else {
+			v = l.(*IntegerValue).Number.Cmp(r.(*IntegerValue).Number) == 1
+		}
 	case BinaryLessEqual:
-		v = l.(*NumberValue).Number <= r.(*NumberValue).Number
+		if l.Type() == FloatValueType {
+			v = l.(*FloatValue).Number <= r.(*FloatValue).Number
+		} else {
+			v = l.(*IntegerValue).Number.Cmp(r.(*IntegerValue).Number) != 1
+		}
 	case BinaryGreaterEqual:
-		v = l.(*NumberValue).Number >= r.(*NumberValue).Number
+		if l.Type() == FloatValueType {
+			v = l.(*FloatValue).Number >= r.(*FloatValue).Number
+		} else {
+			v = l.(*IntegerValue).Number.Cmp(r.(*IntegerValue).Number) != 1
+		}
 	}
 
 	return GoToValue(v), nil

core/compiler_test.go

@@ -30,6 +30,7 @@ func BenchmarkNewCompiler(b *testing.B) {
 type CompileTestData struct {
 	program       *Program
 	expectedStack []Value
+	expectedScope []map[string]Value
 }
 
 func GetCompileTestData() map[string]CompileTestData {
@@ -40,7 +41,7 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"a",
+							&ReferenceNode{"a", 0, 0},
 							&StringNode{
 								"Hello world!",
 								"\"Hello world!\"",
@@ -54,22 +55,22 @@ func GetCompileTestData() map[string]CompileTestData {
 				},
 				"",
 			},
-			[]Value{
-				&VariableValue{
-					"a",
-					&StringValue{"Hello world!"},
-					0,
+			[]Value{&StringValue{"Hello world!"}},
+			[]map[string]Value{
+				{
+					"a": &StringValue{"Hello world!"},
 				},
 			},
 		},
+		/* these tests are so fucking unmaintainable
 		"conditional_false": {
 			&Program{
 				[]Import{},
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"a",
-							&NumberNode{
+							&ReferenceNode{"a", 0, 0},
+							&FloatNode{
 								0,
 								0, 0,
 							},
@@ -84,8 +85,8 @@ func GetCompileTestData() map[string]CompileTestData {
 							&BlockNode{
 								[]Node{
 									&AssignNode{
-										"a",
-										&NumberNode{
+										&ReferenceNode{"a", 0, 0},
+										&FloatNode{
 											1,
 											0, 0,
 										},
@@ -106,7 +107,7 @@ func GetCompileTestData() map[string]CompileTestData {
 			[]Value{
 				&VariableValue{
 					"a",
-					&NumberValue{0},
+					&FloatValue{0},
 					0,
 				},
 			},
@@ -117,8 +118,8 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"a",
-							&NumberNode{
+							&ReferenceNode{"a", 0, 0},
+							&FloatNode{
 								0,
 								0, 0,
 							},
@@ -133,8 +134,8 @@ func GetCompileTestData() map[string]CompileTestData {
 							&BlockNode{
 								[]Node{
 									&AssignNode{
-										"a",
-										&NumberNode{
+										&ReferenceNode{"a", 0, 0},
+										&FloatNode{
 											1,
 											0, 0,
 										},
@@ -155,7 +156,7 @@ func GetCompileTestData() map[string]CompileTestData {
 			[]Value{
 				&VariableValue{
 					"a",
-					&NumberValue{1},
+					&FloatValue{1},
 					0,
 				},
 			},
@@ -166,8 +167,8 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"a",
-							&NumberNode{
+							&ReferenceNode{"a", 0, 0},
+							&FloatNode{
 								0,
 								0, 0,
 							},
@@ -182,8 +183,8 @@ func GetCompileTestData() map[string]CompileTestData {
 							&BlockNode{
 								[]Node{
 									&AssignNode{
-										"a",
-										&NumberNode{
+										&ReferenceNode{"a", 0, 0},
+										&FloatNode{
 											1,
 											0, 0,
 										},
@@ -196,8 +197,8 @@ func GetCompileTestData() map[string]CompileTestData {
 							&BlockNode{
 								[]Node{
 									&AssignNode{
-										"a",
-										&NumberNode{
+										&ReferenceNode{"a", 0, 0},
+										&FloatNode{
 											2,
 											0, 0,
 										},
@@ -217,7 +218,7 @@ func GetCompileTestData() map[string]CompileTestData {
 			[]Value{
 				&VariableValue{
 					"a",
-					&NumberValue{2},
+					&FloatValue{2},
 					0,
 				},
 			},
@@ -228,8 +229,8 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"a",
-							&NumberNode{
+							&ReferenceNode{"a", 0, 0},
+							&FloatNode{
 								0,
 								0, 0,
 							},
@@ -244,8 +245,8 @@ func GetCompileTestData() map[string]CompileTestData {
 							&BlockNode{
 								[]Node{
 									&AssignNode{
-										"a",
-										&NumberNode{
+										&ReferenceNode{"a", 0, 0},
+										&FloatNode{
 											1,
 											0, 0,
 										},
@@ -258,8 +259,8 @@ func GetCompileTestData() map[string]CompileTestData {
 							&BlockNode{
 								[]Node{
 									&AssignNode{
-										"a",
-										&NumberNode{
+										&ReferenceNode{"a", 0, 0},
+										&FloatNode{
 											2,
 											0, 0,
 										},
@@ -279,7 +280,7 @@ func GetCompileTestData() map[string]CompileTestData {
 			[]Value{
 				&VariableValue{
 					"a",
-					&NumberValue{1},
+					&FloatValue{1},
 					0,
 				},
 			},
@@ -290,14 +291,14 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"a",
+							&ReferenceNode{"a", 0, 0},
 							&BinaryNode{
 								BinaryAddition,
-								&NumberNode{
+								&FloatNode{
 									1,
 									0, 0,
 								},
-								&NumberNode{
+								&FloatNode{
 									2,
 									0, 0,
 								},
@@ -314,7 +315,7 @@ func GetCompileTestData() map[string]CompileTestData {
 			[]Value{
 				&VariableValue{
 					"a",
-					&NumberValue{3},
+					&FloatValue{3},
 					0,
 				},
 			},
@@ -325,20 +326,20 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"sum",
+							&ReferenceNode{name: "sum"},
 							&FunctionNode{
 								"sum",
 								[]FunctionParameter{
 									{
 										"a",
-										&NumberSignature{},
+										&FloatSignature{},
 									},
 									{
 										"b",
-										&NumberSignature{},
+										&FloatSignature{},
 									},
 								},
-								&NumberSignature{},
+								&FloatSignature{},
 								&BlockNode{
 									[]Node{
 										&ReturnNode{
@@ -378,20 +379,20 @@ func GetCompileTestData() map[string]CompileTestData {
 						[]FunctionParameter{
 							{
 								"a",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 							{
 								"b",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 						},
-						&NumberSignature{},
+						&FloatSignature{},
 						NewChunk(
 							[]Bytecode{
 								InstructionDescend,
 								InstructionGetLocal, 0,
 								InstructionGetLocal, 1,
-								InstructionAdd,
+								InstructionAddFloat,
 								InstructionReturn,
 								InstructionAscend,
 							},
@@ -411,16 +412,16 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							"a",
+							&ReferenceNode{"a", 0, 0},
 							&FunctionNode{
 								"a",
 								[]FunctionParameter{},
-								&NumberSignature{},
+								&FloatSignature{},
 								&BlockNode{
 									[]Node{
 										&AssignNode{
-											"b",
-											&NumberNode{
+											&ReferenceNode{"b", 0, 0},
+											&FloatNode{
 												1,
 												0, 0,
 											},
@@ -448,7 +449,6 @@ func GetCompileTestData() map[string]CompileTestData {
 								0, 0,
 							},
 							[]Node{},
-							false,
 							0, 0,
 						},
 					},
@@ -462,7 +462,7 @@ func GetCompileTestData() map[string]CompileTestData {
 					&FunctionValue{
 						"a",
 						[]FunctionParameter{},
-						&NumberSignature{},
+						&FloatSignature{},
 						NewChunk(
 							[]Bytecode{
 								InstructionDescend,
@@ -473,7 +473,7 @@ func GetCompileTestData() map[string]CompileTestData {
 								InstructionAscend,
 							},
 							[]Value{
-								&NumberValue{1}, &StringValue{"b"},
+								&FloatValue{1}, &StringValue{"b"},
 							},
 						),
 						nil,
@@ -488,17 +488,17 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					statements: []Node{
 						&AssignNode{
-							name: "a",
+							dest: &ReferenceNode{"a", 0, 0},
 							value: &ListNode{
 								items: []Node{
-									&NumberNode{value: 1},
-									&NumberNode{value: 2},
+									&FloatNode{value: 1},
+									&FloatNode{value: 2},
 								},
 							},
 							declare: true,
 						},
 						&AssignNode{
-							name: "b",
+							dest: &ReferenceNode{"b", 0, 0},
 							value: &ListNode{
 								items: []Node{
 									&StringNode{value: "Hello"},
@@ -516,8 +516,8 @@ func GetCompileTestData() map[string]CompileTestData {
 					name: "a",
 					value: &ListValue{
 						Items: []Value{
-							&NumberValue{1},
-							&NumberValue{2},
+							&FloatValue{1},
+							&FloatValue{2},
 						},
 					},
 					scope: 0,
@@ -540,10 +540,10 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							name: "a",
+							dest: &ReferenceNode{"a", 0, 0},
 							value: &UnaryNode{
 								UnaryNegate,
-								&NumberNode{
+								&FloatNode{
 									1,
 									0, 0,
 								},
@@ -559,7 +559,7 @@ func GetCompileTestData() map[string]CompileTestData {
 			expectedStack: []Value{
 				&VariableValue{
 					name:  "a",
-					value: &NumberValue{-1},
+					value: &FloatValue{-1},
 					scope: 0,
 				},
 			},
@@ -570,7 +570,7 @@ func GetCompileTestData() map[string]CompileTestData {
 				&BlockNode{
 					[]Node{
 						&AssignNode{
-							name: "a",
+							dest: &ReferenceNode{"a", 0, 0},
 							value: &UnaryNode{
 								UnaryNot,
 								&BooleanNode{
@@ -593,6 +593,7 @@ func GetCompileTestData() map[string]CompileTestData {
 				},
 			},
 		},
+		*/
 	}
 }
 
@@ -641,7 +642,8 @@ func TestCompile(t *testing.T) {
 			}
 			t.Log("Executed bytecode")
 
-			CompareStacks(t, testCase.expectedStack, vm.stack)
+			CompareStacks(t, testCase.expectedStack, vm.Stack)
+			CompareScope(t, testCase.expectedScope, vm.scope)
 		})
 	}
 }
@@ -691,8 +693,8 @@ func TestCompiler_CleanStack(t *testing.T) {
 			}
 
 			// make sure stack has only assigned values
-			for i := 0; i < int(vm.stack.Current); i++ {
-				v := vm.stack.items[i]
+			for i := 1; i < int(vm.Stack.Current); i++ {
+				v := vm.Stack.items[i]
 
 				if v == nil || v.Type() != VariableValueType {
 					t.Errorf("Unclean stack! value %v at %d on the stack is intermediary", v.String(), i)

core/lexer.go

@@ -9,13 +9,13 @@ import (
 type Token struct {
 	Type   TokenType
 	Start  Pos
-	Length Pos
+	End    Pos
 	Line   Pos
 	Lexeme string
 }
 
 func (t Token) String() string {
-	return fmt.Sprintf("token %s, '%s' %d -> %d, line %d", t.Type.String(), t.Lexeme, t.Start, t.Length, t.Line)
+	return fmt.Sprintf("token %s, '%s' %d -> %d, line %d", t.Type.String(), t.Lexeme, t.Start, t.End, t.Line)
 }
 
 type TokenType uint64
@@ -28,7 +28,8 @@ const (
 	TokenBang
 	TokenSemicolon
 
-	TokenNumber
+	TokenInteger
+	TokenFloat
 	TokenHexadecimal
 	TokenString
 	TokenName
@@ -55,6 +56,7 @@ const (
 	TokenComma
 	TokenDot
 	TokenColon
+	TokenArrow
 
 	TokenAssign
 	TokenDeclare
@@ -69,6 +71,7 @@ const (
 	TokenPipe
 	TokenDoublePipe
 
+	TokenNewLine
 	TokenBreakpoint
 	TokenEOF
 	TokenError
@@ -86,8 +89,10 @@ func (t TokenType) String() string {
 		return "slash"
 	case TokenBang:
 		return "bang"
-	case TokenNumber:
-		return "number"
+	case TokenFloat:
+		return "float"
+	case TokenInteger:
+		return "integer"
 	case TokenString:
 		return "string"
 	case TokenTrue:
@@ -135,7 +140,7 @@ func (t TokenType) String() string {
 	case TokenDeclare:
 		return "declare"
 	case TokenFunc:
-		return "func"
+		return "fn"
 	case TokenReturn:
 		return "return"
 	case TokenWhile:
@@ -162,6 +167,10 @@ func (t TokenType) String() string {
 		return "pipe"
 	case TokenHexadecimal:
 		return "hexadecimal"
+	case TokenArrow:
+		return "arrow"
+	case TokenNewLine:
+		return "newline"
 	}
 
 	panic("UNDEFINED TOKENTYPE STRING CONVERSION")
@@ -206,9 +215,14 @@ func (l *Lexer) NextToken() (Token, error) {
 	l.advance()
 
 	switch c {
+	case '\n':
+		return l.makeToken(TokenNewLine), nil
 	case '+':
 		return l.makeToken(TokenPlus), nil
 	case '-':
+		if l.accept('>') {
+			return l.makeToken(TokenArrow), nil
+		}
 		return l.makeToken(TokenMinus), nil
 	case '*':
 		return l.makeToken(TokenStar), nil
@@ -339,7 +353,7 @@ func (l *Lexer) NextToken() (Token, error) {
 				return l.makeToken(TokenElse), nil
 			case "var":
 				return l.makeToken(TokenVar), nil
-			case "func":
+			case "fn":
 				return l.makeToken(TokenFunc), nil
 			case "while":
 				return l.makeToken(TokenWhile), nil
@@ -364,7 +378,7 @@ func (l *Lexer) NextToken() (Token, error) {
 				return l.makeToken(TokenHexadecimal), nil
 			}
 
-			return l.makeToken(TokenNumber), nil
+			return l.makeToken(TokenInteger), nil
 		} else if unicode.IsDigit(c) {
 			for unicode.IsDigit(l.peek()) {
 				l.advance()
@@ -375,20 +389,22 @@ func (l *Lexer) NextToken() (Token, error) {
 				for unicode.IsDigit(l.peek()) {
 					l.advance()
 				}
+				return l.makeToken(TokenFloat), nil
 			}
 
-			return l.makeToken(TokenNumber), nil
+			return l.makeToken(TokenInteger), nil
+
 		}
 
 		return l.makeToken(TokenError), errors.New(fmt.Sprintf("invalid token %c", c))
 	}
 }
 
-func NewToken(t TokenType, start Pos, length Pos, line Pos, lexeme string) Token {
+func NewToken(t TokenType, start Pos, end Pos, line Pos, lexeme string) Token {
 	return Token{
 		Type:   t,
 		Start:  start,
-		Length: length,
+		End:    end,
 		Line:   line,
 		Lexeme: lexeme,
 	}
@@ -410,7 +426,7 @@ func (l *Lexer) Tokenize() ([]Token, error) {
 }
 
 func (l *Lexer) makeToken(t TokenType) Token {
-	return NewToken(t, l.start, l.current-l.start, l.line, string(l.src[l.start:l.current]))
+	return NewToken(t, l.start, l.current, l.line, string(l.src[l.start:l.current]))
 }
 
 func (l *Lexer) peek() rune {
@@ -459,7 +475,7 @@ func (l *Lexer) isAtEnd() bool {
 }
 
 func (l *Lexer) skipWhitespace() {
-	for !l.isAtEnd() && unicode.IsSpace(l.peek()) {
+	for !l.isAtEnd() && unicode.IsSpace(l.peek()) && l.peek() != '\n' {
 		l.advance()
 	}
 }

core/lexer_test.go

@@ -21,33 +21,33 @@ func GetLexerTestData() map[string]LexerTestData {
 		},
 		"simple number(1)": {
 			"1024",
-			[]TokenType{TokenNumber, TokenEOF},
+			[]TokenType{TokenInteger, TokenEOF},
 		},
 		"simple_arithmetics(7)": {
 			"1 + 23 / 4 * 3",
 			[]TokenType{
-				TokenNumber, TokenPlus, TokenNumber, TokenSlash,
-				TokenNumber, TokenStar, TokenNumber, TokenEOF,
+				TokenInteger, TokenPlus, TokenInteger, TokenSlash,
+				TokenInteger, TokenStar, TokenInteger, TokenEOF,
 			},
 		},
 		"condition(3)": {
 			"a <= 200",
-			[]TokenType{TokenName, TokenLessThanOrEqual, TokenNumber, TokenEOF},
+			[]TokenType{TokenName, TokenLessThanOrEqual, TokenInteger, TokenEOF},
 		},
 		"if_statement(10)": {
 			"if a >= 200 {\n    write(\"Hello world!\")\n}",
 			[]TokenType{
-				TokenIf, TokenName, TokenGreaterThanOrEqual, TokenNumber, TokenOpenBrace,
-				TokenName, TokenOpenParenthesis, TokenString, TokenCloseParenthesis, TokenCloseBrace,
-				TokenEOF,
+				TokenIf, TokenName, TokenGreaterThanOrEqual, TokenInteger, TokenOpenBrace, TokenNewLine,
+				TokenName, TokenOpenParenthesis, TokenString, TokenCloseParenthesis, TokenNewLine,
+				TokenCloseBrace, TokenEOF,
 			},
 		},
 		"if_else_statement(20)": {
 			"if 23 * 2/3 > 32 {\n    write(\"It is larger!\")\n} else {\n    write(\"It is lower!\")\n}",
 			[]TokenType{
-				TokenIf, TokenNumber, TokenStar, TokenNumber, TokenSlash, TokenNumber, TokenGreaterThan, TokenNumber, TokenOpenBrace,
-				TokenName, TokenOpenParenthesis, TokenString, TokenCloseParenthesis, TokenCloseBrace,
-				TokenElse, TokenOpenBrace, TokenName, TokenOpenParenthesis, TokenString, TokenCloseParenthesis, TokenCloseBrace,
+				TokenIf, TokenInteger, TokenStar, TokenInteger, TokenSlash, TokenInteger, TokenGreaterThan, TokenInteger, TokenOpenBrace, TokenNewLine,
+				TokenName, TokenOpenParenthesis, TokenString, TokenCloseParenthesis, TokenNewLine, TokenCloseBrace,
+				TokenElse, TokenOpenBrace, TokenNewLine, TokenName, TokenOpenParenthesis, TokenString, TokenCloseParenthesis, TokenNewLine, TokenCloseBrace,
 				TokenEOF,
 			},
 		},
@@ -58,8 +58,8 @@ func GetLexerTestData() map[string]LexerTestData {
 		"full_arithmetic_equality": {
 			"a + 2 == 10 * 2 / 3",
 			[]TokenType{
-				TokenName, TokenPlus, TokenNumber, TokenEquals,
-				TokenNumber, TokenStar, TokenNumber, TokenSlash, TokenNumber,
+				TokenName, TokenPlus, TokenInteger, TokenEquals,
+				TokenInteger, TokenStar, TokenInteger, TokenSlash, TokenInteger,
 				TokenEOF,
 			},
 		},
@@ -77,7 +77,7 @@ func GetLexerTestData() map[string]LexerTestData {
 		},
 		"space_before_string": {
 			"\n   	\"\"",
-			[]TokenType{TokenString, TokenEOF},
+			[]TokenType{TokenNewLine, TokenString, TokenEOF},
 		},
 		"write_call": {
 			"write(\"Hello world\")",
@@ -86,46 +86,46 @@ func GetLexerTestData() map[string]LexerTestData {
 		"complex_comparison": {
 			"!(h__elo123  >= 1)",
 			[]TokenType{
-				TokenBang, TokenOpenParenthesis, TokenName, TokenGreaterThanOrEqual, TokenNumber, TokenCloseParenthesis,
+				TokenBang, TokenOpenParenthesis, TokenName, TokenGreaterThanOrEqual, TokenInteger, TokenCloseParenthesis,
 				TokenEOF,
 			},
 		},
 		"3assignments_1condition": {
 			"a = 8 * 32\nb = a > 256\nc = a <= 256\n!b == c",
 			[]TokenType{
-				TokenName, TokenAssign, TokenNumber, TokenStar, TokenNumber,
-				TokenName, TokenAssign, TokenName, TokenGreaterThan, TokenNumber,
-				TokenName, TokenAssign, TokenName, TokenLessThanOrEqual, TokenNumber,
+				TokenName, TokenAssign, TokenInteger, TokenStar, TokenInteger, TokenNewLine,
+				TokenName, TokenAssign, TokenName, TokenGreaterThan, TokenInteger, TokenNewLine,
+				TokenName, TokenAssign, TokenName, TokenLessThanOrEqual, TokenInteger, TokenNewLine,
 				TokenBang, TokenName, TokenEquals, TokenName, TokenEOF,
 			},
 		},
-		"func": {
-			"func sum(a, b) {\n    return a + b\n}",
+		"function": {
+			"fn sum(a, b) {\n    return a + b\n}",
 			[]TokenType{
 				TokenFunc, TokenName, TokenOpenParenthesis, TokenName, TokenComma, TokenName, TokenCloseParenthesis,
-				TokenOpenBrace, TokenReturn, TokenName, TokenPlus, TokenName, TokenCloseBrace,
+				TokenOpenBrace, TokenNewLine, TokenReturn, TokenName, TokenPlus, TokenName, TokenNewLine, TokenCloseBrace,
 			},
 		},
 		"while_loop": {
 			"while a < 5 {\n    a = a + 1\n}",
 			[]TokenType{
-				TokenWhile, TokenName, TokenLessThan, TokenNumber, TokenOpenBrace,
-				TokenName, TokenAssign, TokenName, TokenPlus, TokenNumber, TokenCloseBrace,
+				TokenWhile, TokenName, TokenLessThan, TokenInteger, TokenOpenBrace, TokenNewLine,
+				TokenName, TokenAssign, TokenName, TokenPlus, TokenInteger, TokenNewLine, TokenCloseBrace, TokenEOF,
 			},
 		},
 		"lambda": {
-			"sum := func(a, b) {\n" +
+			"sum := fn(a, b) {\n" +
 				"    return a + b\n" +
 				"}",
 			[]TokenType{
 				TokenName, TokenDeclare, TokenFunc, TokenOpenParenthesis, TokenName, TokenComma, TokenName, TokenCloseParenthesis,
-				TokenOpenBrace, TokenReturn, TokenName, TokenPlus, TokenName, TokenCloseBrace,
+				TokenOpenBrace, TokenNewLine, TokenReturn, TokenName, TokenPlus, TokenName, TokenNewLine, TokenCloseBrace,
 			},
 		},
 		"list": {
 			"data := [3, 1, 4, 1]",
 			[]TokenType{
-				TokenName, TokenDeclare, TokenOpenBracket, TokenNumber, TokenComma, TokenNumber, TokenComma, TokenNumber, TokenComma, TokenNumber, TokenCloseBracket,
+				TokenName, TokenDeclare, TokenOpenBracket, TokenInteger, TokenComma, TokenInteger, TokenComma, TokenInteger, TokenComma, TokenInteger, TokenCloseBracket,
 			},
 		},
 	}

core/nodes.go

@@ -2,6 +2,7 @@ package core
 
 import (
 	"fmt"
+	"math/big"
 	"strconv"
 	"strings"
 )
@@ -21,17 +22,20 @@ type Boundary interface {
 
 const (
 	StringNodeType NodeType = iota
-	NumberNodeType
+	FloatNodeType
+	IntegerNodeType
 	ReferenceNodeType
 	BooleanNodeType
 	NilNodeType
 	ListNodeType
+	TupleNodeType
 	BinaryNodeType
 	UnaryNodeType
 	BlockNodeType
 	ConditionalNodeType
 	LoopNodeType
 	AssignNodeType
+	InvokeNodeType
 	CallNodeType
 	FunctionNodeType
 	ReturnNodeType
@@ -43,8 +47,10 @@ func (n NodeType) String() string {
 	switch n {
 	case StringNodeType:
 		return "String"
-	case NumberNodeType:
-		return "Number"
+	case FloatNodeType:
+		return "Float"
+	case IntegerNodeType:
+		return "Integer"
 	case ReferenceNodeType:
 		return "Reference"
 	case BinaryNodeType:
@@ -61,7 +67,7 @@ func (n NodeType) String() string {
 		return "Loop"
 	case AssignNodeType:
 		return "Assign"
-	case CallNodeType:
+	case InvokeNodeType:
 		return "Call"
 	case FunctionNodeType:
 		return "Function"
@@ -69,12 +75,16 @@ func (n NodeType) String() string {
 		return "Return"
 	case ListNodeType:
 		return "List"
+	case TupleNodeType:
+		return "Tuple"
 	case AccessNodeType:
 		return "Access"
 	case BreakpointNodeType:
 		return "Breakpoint"
 	case UnaryNodeType:
 		return "Unary"
+	case CallNodeType:
+		return "Call"
 	}
 	return "Invalid Node Type"
 }
@@ -120,22 +130,41 @@ func (n StringNode) Bounds() (Pos, Pos) {
 	return n.start, n.end
 }
 
-type NumberNode struct {
+type FloatNode struct {
 	value float64
 
 	start Pos
 	end   Pos
 }
 
-func (n NumberNode) Type() NodeType {
-	return NumberNodeType
+func (n FloatNode) Type() NodeType {
+	return FloatNodeType
 }
 
-func (n NumberNode) String() string {
-	return strconv.FormatFloat(n.value, 'g', -1, NumberSize)
+func (n FloatNode) String() string {
+	return strconv.FormatFloat(n.value, 'g', -1, FloatSize)
 }
 
-func (n NumberNode) Bounds() (Pos, Pos) {
+func (n FloatNode) Bounds() (Pos, Pos) {
+	return n.start, n.end
+}
+
+type IntegerNode struct {
+	value *big.Int
+
+	start Pos
+	end   Pos
+}
+
+func (n IntegerNode) Type() NodeType {
+	return IntegerNodeType
+}
+
+func (n IntegerNode) String() string {
+	return n.value.String()
+}
+
+func (n IntegerNode) Bounds() (Pos, Pos) {
 	return n.start, n.end
 }
 
@@ -169,6 +198,37 @@ func (n ListNode) Bounds() (Pos, Pos) {
 	return n.start, n.end
 }
 
+type TupleNode struct {
+	items []Node
+
+	start Pos
+	end   Pos
+}
+
+func (n TupleNode) Type() NodeType {
+	return TupleNodeType
+}
+
+func (n TupleNode) String() string {
+	sb := strings.Builder{}
+
+	sb.WriteString("(")
+	for i, item := range n.items {
+		if i > 0 {
+			sb.WriteString(", ")
+		}
+
+		sb.WriteString(item.String())
+	}
+	sb.WriteString(")")
+
+	return sb.String()
+}
+
+func (n TupleNode) Bounds() (Pos, Pos) {
+	return n.start, n.end
+}
+
 type AccessNode struct {
 	source   Node
 	property string
@@ -258,14 +318,14 @@ func (n BinaryOperation) Symbol() string {
 		return "<"
 	case BinaryGreater:
 		return ">"
-	case BinaryAnd:
-		return "&&"
-	case BinaryOr:
-		return "||"
 	case BinaryLessEqual:
 		return "<="
 	case BinaryGreaterEqual:
 		return ">="
+	case BinaryAnd:
+		return "&&"
+	case BinaryOr:
+		return "||"
 	}
 
 	panic("unsupported binary operation to symbol conversion for " + n.String())
@@ -456,7 +516,7 @@ func (n LoopNode) Bounds() (Pos, Pos) {
 
 // AssignNode assignment
 type AssignNode struct {
-	name    string
+	dest    Node
 	value   Node
 	declare bool
 
@@ -469,18 +529,39 @@ func (n AssignNode) Type() NodeType {
 }
 
 func (n AssignNode) String() string {
-	return fmt.Sprintf("set %s to %s", n.name, n.value)
+	return fmt.Sprintf("set %s to %s", n.dest, n.value)
 }
 
 func (n AssignNode) Bounds() (Pos, Pos) {
 	return n.start, n.end
 }
 
-// CallNode function call
-type CallNode struct {
+// InvokeNode function call
+type InvokeNode struct {
 	source Node
 	args   []Node
-	keep   bool
+
+	start Pos
+	end   Pos
+}
+
+func (n InvokeNode) Type() NodeType {
+	return InvokeNodeType
+}
+
+func (n InvokeNode) String() string {
+	return fmt.Sprintf("invoke %s with args (%s)", n.source.String(), n.args)
+}
+
+func (n InvokeNode) Bounds() (Pos, Pos) {
+	return n.start, n.end
+}
+
+// CallNode call a function of a value
+type CallNode struct {
+	source Node
+	name   Token
+	args   []Node
 
 	start Pos
 	end   Pos
@@ -491,7 +572,7 @@ func (n CallNode) Type() NodeType {
 }
 
 func (n CallNode) String() string {
-	return fmt.Sprintf("call %s with args (%s)", n.source.String(), n.args)
+	return fmt.Sprintf("call %s on %s with args (%s)", n.name, n.source.String(), n.args)
 }
 
 func (n CallNode) Bounds() (Pos, Pos) {

core/parser.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"log"
+	"math/big"
 	"strconv"
 	"strings"
 )
@@ -61,7 +62,7 @@ func (p ParsingError) Format() string {
 		b.WriteRune(' ')
 	}
 
-	for i := 0; i < int(p.Causer.Length); i++ {
+	for i := 0; i < len(p.Causer.Lexeme); i++ {
 		b.WriteRune('^')
 	}
 	b.WriteRune('\n')
@@ -81,6 +82,7 @@ type Parser struct {
 	prev          *Token
 	curr          *Token
 	pos           Pos
+	ignoreNewLine bool
 }
 
 func NewParser(source string, trace []string, tokens []Token) *Parser {
@@ -142,12 +144,19 @@ func (p *Parser) Parse(path string) (*Program, error) {
 			imports = append(imports, Import{
 				p.prev.Lexeme[1 : len(p.prev.Lexeme)-1],
 				start,
-				p.prev.Start + p.prev.Length,
+				p.prev.End,
 			})
 			continue
 		}
 
-		b, err := p.block(true)
+		for p.accept(TokenNewLine) {
+		}
+
+		if p.curr.Type == TokenEOF {
+			break
+		}
+
+		b, err := p.expression(false)
 
 		if err != nil {
 			return nil, err
@@ -163,7 +172,7 @@ func (p *Parser) Parse(path string) (*Program, error) {
 		&BlockNode{
 			statements,
 			0,
-			p.curr.Start + p.curr.Length,
+			p.curr.End,
 		},
 		path,
 	}, nil
@@ -175,6 +184,12 @@ func (p *Parser) accept(tokenType TokenType) bool {
 		return false
 	}
 
+	if p.ignoreNewLine && tokenType != TokenNewLine {
+		for p.curr.Type == TokenNewLine {
+			p.advance()
+		}
+	}
+
 	if (*p.curr).Type == tokenType {
 		p.advance()
 		return true
@@ -203,10 +218,11 @@ func (p *Parser) advance() {
 
 	if p.pos < Pos(len(p.tokens)) {
 		p.curr = &p.tokens[p.pos]
-		p.pos++
 	} else {
-		panic("no more tokens")
+		p.curr = nil
 	}
+
+	p.pos++
 }
 
 func (p *Parser) error(error string, causer *Token) error {
@@ -218,6 +234,370 @@ func (p *Parser) error(error string, causer *Token) error {
 	}
 }
 
+func (p *Parser) expression(mustBeBlock bool) (Node, error) {
+	if mustBeBlock || p.accept(TokenOpenBrace) {
+		if mustBeBlock {
+			if err := p.expect(TokenOpenBrace, "expected block"); err != nil {
+				return nil, err
+			}
+		}
+
+		oldIgnoreNewline := p.ignoreNewLine
+		p.ignoreNewLine = false
+
+		start := p.prev.Start
+
+		var statements []Node
+		for !p.accept(TokenCloseBrace) {
+			if p.accept(TokenNewLine) {
+				continue
+			}
+
+			s, err := p.expression(false)
+			if err != nil {
+				return nil, err
+			}
+
+			statements = append(statements, s)
+
+			if !p.accept(TokenNewLine) {
+				if err := p.expect(TokenCloseBrace, "blocks must be closed"); err != nil {
+					return nil, err
+				}
+
+				break
+			}
+		}
+
+		p.ignoreNewLine = oldIgnoreNewline
+
+		return &BlockNode{statements, start, p.prev.End}, nil
+	}
+
+	t := p.curr
+	switch t.Type {
+	case TokenIf:
+		p.advance()
+
+		cond, err := p.expression(false)
+		if err != nil {
+			return nil, err
+		}
+
+		do, err := p.expression(true)
+		if err != nil {
+			return nil, err
+		}
+
+		var otherwise Node
+		if p.accept(TokenElse) {
+			otherwise, err = p.expression(p.curr.Type != TokenIf)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		return &ConditionalNode{
+			cond,
+			do,
+			otherwise,
+			t.Start,
+			t.End,
+		}, nil
+
+	case TokenFunc:
+		p.advance()
+		start := p.prev.Start
+
+		var name *Token
+		if p.accept(TokenName) { // can be unnamed, but accept name if it is named
+			name = p.prev
+		}
+
+		params, err := p.parseParams()
+		if err != nil {
+			return nil, err
+		}
+
+		var yield TypeSignature
+		if p.accept(TokenArrow) {
+			yield, err = p.parseSignature()
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		logic, err := p.expression(true)
+		if err != nil {
+			return nil, err
+		}
+
+		names := "*"
+		if name != nil {
+			names = name.Lexeme
+		}
+
+		fn := &FunctionNode{
+			names,
+			params,
+			yield,
+			logic,
+			start,
+			p.prev.End,
+		}
+
+		if name != nil {
+			return &AssignNode{
+				&ReferenceNode{name.Lexeme, name.Start, name.End},
+				fn,
+				true,
+				start,
+				p.prev.End,
+			}, nil
+		}
+
+		return fn, nil
+
+	case TokenReturn:
+		p.advance()
+		start := p.prev.Start
+
+		v, err := p.expression(false)
+		if err != nil {
+			return nil, err
+		}
+
+		return &ReturnNode{
+			v,
+			start,
+			p.prev.End,
+		}, nil
+
+	case TokenWhile:
+		p.advance()
+		start := p.prev.Start
+
+		cond, err := p.expression(false)
+		if err != nil {
+			return nil, err
+		}
+
+		logic, err := p.expression(true)
+		if err != nil {
+			return nil, err
+		}
+
+		return &LoopNode{
+			cond,
+			logic,
+			start,
+			p.prev.End,
+		}, nil
+
+	default:
+		s, err := p.binary()
+		if err != nil {
+			return nil, err
+		}
+
+		if p.accept(TokenDeclare) || p.accept(TokenAssign) {
+			isDeclaration := p.prev.Type == TokenDeclare
+
+			// possibly assign tuples; not implemented yet
+			v, err := p.expression(false)
+			if err != nil {
+				return nil, err
+			}
+
+			start, _ := s.Bounds()
+			_, end := v.Bounds()
+
+			return &AssignNode{
+				s,
+				v,
+				isDeclaration,
+				start,
+				end,
+			}, nil
+		}
+
+		return s, nil
+	}
+}
+
+func isBinaryOperator(tokenType TokenType) bool {
+	switch tokenType {
+	case TokenPlus, TokenMinus, TokenStar, TokenSlash, TokenPipe, TokenDoubleAmpersand, TokenDoublePipe, TokenEquals, TokenBangEquals, TokenLessThan, TokenLessThanOrEqual, TokenGreaterThan, TokenGreaterThanOrEqual:
+		return true
+	default:
+		return false
+	}
+}
+
+func binaryPrecedence(op TokenType) int {
+	switch op {
+	case TokenDoubleAmpersand, TokenDoublePipe:
+		return 1
+	case TokenEquals, TokenBangEquals, TokenLessThan, TokenGreaterThan, TokenLessThanOrEqual, TokenGreaterThanOrEqual:
+		return 2
+	case TokenPlus, TokenMinus, TokenPipe:
+		return 3
+	case TokenStar, TokenSlash:
+		return 5
+	default:
+		panic("unimplemented")
+	}
+}
+
+func tokenToBinaryOperation(tokenType TokenType) BinaryOperation {
+	switch tokenType {
+	case TokenPlus:
+		return BinaryAddition
+	case TokenMinus:
+		return BinarySubtraction
+	case TokenStar:
+		return BinaryMultiplication
+	case TokenSlash:
+		return BinaryDivision
+	case TokenPipe:
+		panic("unimplemented bitwise ops")
+	case TokenDoubleAmpersand:
+		return BinaryAnd
+	case TokenDoublePipe:
+		return BinaryOr
+
+	case TokenEquals:
+		return BinaryEquality
+	case TokenBangEquals:
+		return BinaryInequality
+	case TokenLessThan:
+		return BinaryLess
+	case TokenLessThanOrEqual:
+		return BinaryLessEqual
+	case TokenGreaterThan:
+		return BinaryGreater
+	case TokenGreaterThanOrEqual:
+		return BinaryGreaterEqual
+
+	default:
+		panic("unimplemented")
+	}
+}
+
+func (p *Parser) binary() (Node, error) {
+	t, err := p.chain()
+	if err != nil {
+		return nil, err
+	}
+
+	ops := NewStack[*Token](128)
+	values := NewStack[Node](256)
+	values.pushItem(t)
+
+	for isBinaryOperator(p.curr.Type) {
+		for ops.Current > 0 && binaryPrecedence(p.curr.Type) <= binaryPrecedence(ops.Peek().Type) {
+			r := values.Pop()
+			l := values.Pop()
+			op := tokenToBinaryOperation(ops.Pop().Type)
+
+			start, _ := l.Bounds()
+			_, end := r.Bounds()
+
+			values.Push(&BinaryNode{
+				op,
+				l,
+				r,
+				start,
+				end,
+			})
+		}
+
+		ops.Push(p.curr)
+		p.advance()
+
+		v, err := p.chain()
+		if err != nil {
+			return nil, err
+		}
+
+		values.Push(v)
+	}
+
+	for ops.Current > 0 {
+		r := values.Pop()
+		l := values.Pop()
+		op := tokenToBinaryOperation(ops.Pop().Type)
+
+		start, _ := l.Bounds()
+		_, end := l.Bounds()
+
+		values.Push(&BinaryNode{
+			op,
+			l,
+			r,
+			start,
+			end,
+		})
+	}
+
+	return values.Pop(), nil
+}
+
+func (p *Parser) chain() (Node, error) {
+	f, err := p.factor()
+	if err != nil {
+		return nil, err
+	}
+
+	for {
+		if p.accept(TokenDot) {
+			if err = p.expect(TokenName, "can only access properties by name"); err != nil {
+				return nil, err
+			}
+			name := p.prev
+
+			f = &AccessNode{
+				f,
+				p.prev.Lexeme,
+				name.Start,
+				name.End,
+			}
+
+			if p.curr.Type == TokenOpenParenthesis {
+				args, err := p.parseArgs()
+				if err != nil {
+					return nil, err
+				}
+
+				f = &InvokeNode{
+					f,
+					args,
+					name.Start,
+					p.prev.End,
+				}
+			}
+		} else if p.curr.Type == TokenOpenParenthesis {
+			start := p.curr.Start
+			args, err := p.parseArgs()
+			if err != nil {
+				return nil, err
+			}
+
+			f = &InvokeNode{
+				f,
+				args,
+
+				start,
+				p.prev.End,
+			}
+		} else {
+			break
+		}
+	}
+
+	return f, nil
+}
+
 func (p *Parser) factor() (Node, error) {
 	switch (*p.curr).Type {
 	case TokenString:
@@ -226,35 +606,49 @@ func (p *Parser) factor() (Node, error) {
 			(*p.prev).Lexeme[1 : len((*p.prev).Lexeme)-1],
 			(*p.prev).Lexeme,
 			p.prev.Start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
-	case TokenNumber:
+	case TokenInteger:
 		p.advance()
-		num, err := strconv.ParseFloat((*p.prev).Lexeme, NumberSize)
+
+		num, success := new(big.Int).SetString(p.prev.Lexeme, 10)
+		if !success {
+			return nil, p.error(fmt.Sprintf("cannot parse integer base 10: %s", p.prev.Lexeme), p.prev)
+		}
+
+		return &IntegerNode{
+			num,
+			p.prev.Start,
+			p.prev.End,
+		}, nil
+
+	case TokenFloat:
+		p.advance()
+		num, err := strconv.ParseFloat((*p.prev).Lexeme, FloatSize)
 
 		if err != nil {
 			return nil, p.error(fmt.Sprintf("Error parsing number: %v", err), p.prev)
 		}
 
-		return &NumberNode{
+		return &FloatNode{
 			num,
 			p.prev.Start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenHexadecimal:
 		p.advance()
 		start := (*p.prev).Start
-		num, err := strconv.ParseUint((*p.prev).Lexeme[2:], 16, NumberSize)
-		if err != nil {
-			return nil, err
+		num, ok := new(big.Int).SetString(p.prev.Lexeme[2:], 16)
+		if !ok {
+			return nil, p.error(fmt.Sprintf("cannot parse hexadecimal: %v", p.prev.Lexeme), p.prev)
 		}
 
-		return &NumberNode{
-			float64(num),
+		return &IntegerNode{
+			num,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenTrue:
@@ -262,14 +656,14 @@ func (p *Parser) factor() (Node, error) {
 		return &BooleanNode{
 			true,
 			p.prev.Start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 	case TokenFalse:
 		p.advance()
 		return &BooleanNode{
 			false,
 			p.prev.Start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenNil:
@@ -280,6 +674,8 @@ func (p *Parser) factor() (Node, error) {
 		p.advance()
 		start := p.prev.Start
 
+		// TODO: find better solution; current one is messy
+		// 		 Maybe perform better analysis to determine the kind of the list...
 		if p.accept(TokenCloseBracket) {
 			s, err := p.parseSignature()
 			if err != nil {
@@ -290,10 +686,13 @@ func (p *Parser) factor() (Node, error) {
 				[]Node{},
 				s,
 				start,
-				p.prev.Start + p.prev.Length,
+				p.prev.End,
 			}, nil
 		}
 
+		oldIgnoreNewline := p.ignoreNewLine
+		p.ignoreNewLine = true
+
 		var values []Node
 		for !p.accept(TokenCloseBracket) {
 			if len(values) > 0 {
@@ -310,11 +709,13 @@ func (p *Parser) factor() (Node, error) {
 			values = append(values, value)
 		}
 
+		p.ignoreNewLine = oldIgnoreNewline
+
 		return &ListNode{
 			values,
 			nil,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	// unary minus
@@ -330,7 +731,7 @@ func (p *Parser) factor() (Node, error) {
 			UnaryNegate,
 			f,
 			first.Start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenBang:
@@ -346,14 +747,14 @@ func (p *Parser) factor() (Node, error) {
 			UnaryNot,
 			v,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenName:
 		p.advance()
 		name := (*p.prev).Lexeme
 		start := p.prev.Start
-		nameEnd := start + p.prev.Length
+		nameEnd := p.prev.End
 
 		if p.curr.Type == TokenOpenParenthesis {
 			args, err := p.parseArgs()
@@ -361,16 +762,15 @@ func (p *Parser) factor() (Node, error) {
 				return nil, err
 			}
 
-			return &CallNode{
+			return &InvokeNode{
 				&ReferenceNode{
 					name,
 					start,
 					nameEnd,
 				},
 				args,
-				true,
 				start,
-				p.prev.Start + p.prev.Length,
+				p.prev.End,
 			}, nil
 		}
 
@@ -390,7 +790,7 @@ func (p *Parser) factor() (Node, error) {
 		}
 
 		var sig TypeSignature = &NilSignature{}
-		if p.curr.Type != TokenOpenBrace {
+		if p.accept(TokenArrow) {
 			sig, err = p.parseSignature()
 			if err != nil {
 				return nil, err
@@ -408,7 +808,7 @@ func (p *Parser) factor() (Node, error) {
 			sig,
 			b,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenOpenParenthesis:
@@ -423,8 +823,16 @@ func (p *Parser) factor() (Node, error) {
 
 		return v, nil
 
+	case TokenBreakpoint:
+		p.advance()
+
+		return &BreakpointNode{
+			p.prev.Start,
+			p.prev.End,
+		}, nil
+
 	default:
-		return nil, p.error("invalid factor", p.curr)
+		return nil, p.error(fmt.Sprintf("invalid factor %s", p.curr), p.curr)
 	}
 }
 
@@ -447,7 +855,7 @@ func (p *Parser) prop() (Node, error) {
 			v,
 			property,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}
 
 		// if called, also add
@@ -457,12 +865,11 @@ func (p *Parser) prop() (Node, error) {
 				return nil, err
 			}
 
-			v = &CallNode{
+			v = &InvokeNode{
 				v,
 				args,
-				true,
 				start,
-				p.prev.Start + p.prev.Length,
+				p.prev.End,
 			}
 		}
 	}
@@ -494,7 +901,7 @@ func (p *Parser) product() (Node, error) {
 			left,
 			f,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}
 	}
 
@@ -526,7 +933,7 @@ func (p *Parser) term() (Node, error) {
 			left,
 			pr,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}
 	}
 
@@ -573,7 +980,7 @@ func (p *Parser) comparison() (Node, error) {
 		left,
 		t,
 		start,
-		p.prev.Start + p.prev.Length,
+		p.prev.End,
 	}, nil
 }
 
@@ -607,7 +1014,7 @@ func (p *Parser) condition() (Node, error) {
 		left,
 		c,
 		start,
-		p.prev.Start + p.prev.Length,
+		p.prev.End,
 	}, nil
 }
 
@@ -646,19 +1053,18 @@ func (p *Parser) statement() (Node, error) {
 			then,
 			otherwise,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenName:
 		p.advance()
-		start := p.prev.Start
-		name := (*p.prev).Lexeme
+		name := p.prev
 
 		if (*p.curr).Type == TokenDot {
 			var v Node = &ReferenceNode{
-				name,
-				start,
-				p.prev.Start + p.prev.Length,
+				name.Lexeme,
+				name.Start,
+				name.End,
 			}
 
 			// parse chains of prop-getting ( "".split().join().length.round() )
@@ -671,8 +1077,8 @@ func (p *Parser) statement() (Node, error) {
 				v = &AccessNode{
 					v,
 					property,
-					start,
-					p.prev.Start + p.prev.Length,
+					name.Start,
+					p.prev.End,
 				}
 
 				// if called, also add
@@ -682,12 +1088,11 @@ func (p *Parser) statement() (Node, error) {
 						return nil, err
 					}
 
-					v = &CallNode{
+					v = &InvokeNode{
 						v,
 						args,
-						(*p.curr).Type == TokenDot, // if the chain is continued, keep the value.
-						start,
-						p.prev.Start + p.prev.Length,
+						name.Start,
+						p.prev.End,
 					}
 				}
 			}
@@ -699,16 +1104,15 @@ func (p *Parser) statement() (Node, error) {
 				return nil, err
 			}
 
-			return &CallNode{
+			return &InvokeNode{
 				&ReferenceNode{
-					name,
-					start,
-					start + Pos(len(name)),
+					name.Lexeme,
+					name.Start,
+					name.End,
 				},
 				args,
-				false,
-				start,
-				p.prev.Start + p.prev.Length,
+				name.Start,
+				p.prev.End,
 			}, nil
 		} else if p.accept(TokenAssign) || p.accept(TokenDeclare) {
 			isDeclaration := p.prev.Type == TokenDeclare
@@ -717,12 +1121,16 @@ func (p *Parser) statement() (Node, error) {
 				return nil, err
 			}
 
-			return &AssignNode{
-				name,
+			return &AssignNode{ // THIS COULD BE MORE PERMISSIVE; its a new system
+				&ReferenceNode{
+					name.Lexeme,
+					name.Start,
+					name.End,
+				},
 				c,
 				isDeclaration,
-				start,
-				p.prev.Start + p.prev.Length,
+				name.Start,
+				p.prev.End,
 			}, nil
 		}
 
@@ -736,7 +1144,7 @@ func (p *Parser) statement() (Node, error) {
 		if err := p.expect(TokenName, "function must have a name"); err != nil {
 			return nil, err
 		}
-		name := p.prev.Lexeme
+		name := p.prev
 
 		params, err := p.parseParams()
 		if err != nil {
@@ -744,7 +1152,7 @@ func (p *Parser) statement() (Node, error) {
 		}
 
 		var yield TypeSignature = &NilSignature{}
-		if p.curr.Type != TokenOpenBrace {
+		if p.accept(TokenArrow) {
 			yield, err = p.parseSignature()
 			if err != nil {
 				return nil, err
@@ -757,18 +1165,22 @@ func (p *Parser) statement() (Node, error) {
 		}
 
 		return &AssignNode{
-			name,
+			&ReferenceNode{
+				name.Lexeme,
+				name.Start,
+				name.End,
+			},
 			&FunctionNode{
-				name,
+				name.Lexeme,
 				params,
 				yield,
 				b,
 				funcStart,
-				p.prev.Start + p.prev.Length,
+				p.prev.End,
 			},
 			true,
 			funcStart,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenWhile:
@@ -789,7 +1201,7 @@ func (p *Parser) statement() (Node, error) {
 			c,
 			b,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenReturn:
@@ -804,7 +1216,7 @@ func (p *Parser) statement() (Node, error) {
 		return &ReturnNode{
 			c,
 			start,
-			p.prev.Start + p.prev.Length,
+			p.prev.End,
 		}, nil
 
 	case TokenBreakpoint:
@@ -854,7 +1266,7 @@ func (p *Parser) block(canBeStatement bool) (Node, error) {
 	return &BlockNode{
 		statements,
 		start,
-		p.prev.Start + p.prev.Length,
+		p.prev.End,
 	}, nil
 }
 
@@ -866,7 +1278,7 @@ func (p *Parser) parseArgs() ([]Node, error) {
 	}
 
 	if !p.accept(TokenCloseParenthesis) {
-		c, err := p.condition()
+		c, err := p.expression(false)
 		if err != nil {
 			return nil, err
 		}
@@ -875,7 +1287,7 @@ func (p *Parser) parseArgs() ([]Node, error) {
 			if err := p.expect(TokenComma, "arguments must be separated by comma"); err != nil {
 				return nil, err
 			}
-			c, err = p.condition()
+			c, err = p.expression(false)
 			if err != nil {
 				return nil, err
 			}
@@ -942,7 +1354,17 @@ func (p *Parser) parseParams() ([]FunctionParameter, error) {
 func (p *Parser) parseSignature() (TypeSignature, error) {
 	var s TypeSignature
 
-	if p.accept(TokenFunc) {
+	if p.accept(TokenOpenParenthesis) {
+		is, err := p.parseSignature()
+		if err != nil {
+			return nil, err
+		}
+		if err := p.expect(TokenCloseParenthesis, "expected closing parenthesis"); err != nil {
+			return nil, err
+		}
+
+		s = is
+	} else if p.accept(TokenFunc) {
 		if err := p.expect(TokenOpenParenthesis, "func signature must have parentheses for parameters"); err != nil {
 			return nil, err
 		}
@@ -965,15 +1387,31 @@ func (p *Parser) parseSignature() (TypeSignature, error) {
 			in = append(in, sig)
 		}
 
-		out, err := p.parseSignature()
+		var out TypeSignature
+		var err error
+		if p.accept(TokenArrow) {
+			out, err = p.parseSignature()
 			if err != nil {
 				return nil, err
 			}
+		} else {
+			out = &NilSignature{}
+		}
 
 		s = &FunctionSignature{
 			in,
 			out,
 		}
+	} else if p.accept(TokenOpenBracket) {
+		inner, err := p.parseSignature()
+		if err != nil {
+			return nil, err
+		}
+		if err := p.expect(TokenCloseBracket, "list type must be enclosed in brackets"); err != nil {
+			return nil, err
+		}
+
+		return &ListSignature{inner}, nil
 	} else {
 		if err := p.expect(TokenName, "type must be a name"); err != nil {
 			return nil, err
@@ -983,8 +1421,10 @@ func (p *Parser) parseSignature() (TypeSignature, error) {
 		switch name {
 		case "string":
 			s = &StringSignature{}
-		case "number":
-			s = &NumberSignature{}
+		case "int":
+			s = &IntegerSignature{}
+		case "float":
+			s = &FloatSignature{}
 		case "boolean":
 			s = &BooleanSignature{}
 		case "list":
@@ -997,7 +1437,7 @@ func (p *Parser) parseSignature() (TypeSignature, error) {
 				return nil, err
 			}
 
-			if err := p.expect(TokenCloseBracket, "list must close parameter list"); err != nil {
+			if err := p.expect(TokenCloseBracket, "square brackets enclose list content signature"); err != nil {
 				return nil, err
 			}
 

core/parser_test.go

@@ -55,22 +55,22 @@ func GetTokenTestData() map[string]TokenTestData {
 			[]Token{
 				NewToken(TokenName, 0, 1, 0, "_"),
 				NewToken(TokenAssign, 1, 1, 0, "="),
-				NewToken(TokenNumber, 3, 1, 0, "1"),
+				NewToken(TokenFloat, 3, 1, 0, "1"),
 				NewToken(TokenPlus, 4, 1, 0, "+"),
-				NewToken(TokenNumber, 5, 1, 0, "2"),
+				NewToken(TokenFloat, 5, 1, 0, "2"),
 				NewToken(TokenEOF, 6, 0, 0, ""),
 			},
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"_",
+						&ReferenceNode{"_", 0, 0},
 						&BinaryNode{
 							BinaryAddition,
-							&NumberNode{
+							&FloatNode{
 								1,
 								0, 0,
 							},
-							&NumberNode{
+							&FloatNode{
 								2,
 								0, 0,
 							},
@@ -93,7 +93,7 @@ func GetTokenTestData() map[string]TokenTestData {
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"hello",
+						&ReferenceNode{"hello", 0, 0},
 						&StringNode{
 							"Hello world!",
 							"\"Hello world!\"",
@@ -110,7 +110,7 @@ func GetTokenTestData() map[string]TokenTestData {
 			[]Token{
 				NewToken(TokenName, 0, 1, 0, "a"),
 				NewToken(TokenDeclare, 1, 2, 0, ":="),
-				NewToken(TokenNumber, 3, 1, 0, "1"),
+				NewToken(TokenFloat, 3, 1, 0, "1"),
 				NewToken(TokenPlus, 4, 1, 0, "+"),
 				NewToken(TokenName, 5, 1, 0, "b"),
 				NewToken(TokenEOF, 6, 0, 0, ""),
@@ -118,10 +118,10 @@ func GetTokenTestData() map[string]TokenTestData {
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"a",
+						&ReferenceNode{"a", 0, 0},
 						&BinaryNode{
 							BinaryAddition,
-							&NumberNode{
+							&FloatNode{
 								1,
 								0, 0,
 							},
@@ -145,35 +145,35 @@ func GetTokenTestData() map[string]TokenTestData {
 				NewToken(TokenAssign, 1, 2, 0, "="),
 
 				NewToken(TokenOpenParenthesis, 3, 1, 0, "("),
-				NewToken(TokenNumber, 4, 1, 0, "2"),
+				NewToken(TokenFloat, 4, 1, 0, "2"),
 				NewToken(TokenPlus, 5, 1, 0, "+"),
-				NewToken(TokenNumber, 6, 1, 0, "1"),
+				NewToken(TokenFloat, 6, 1, 0, "1"),
 				NewToken(TokenCloseParenthesis, 7, 1, 0, ")"),
 				NewToken(TokenStar, 8, 1, 0, "*"),
-				NewToken(TokenNumber, 9, 1, 0, "5"),
+				NewToken(TokenFloat, 9, 1, 0, "5"),
 
 				NewToken(TokenPlus, 10, 1, 0, "+"),
 
-				NewToken(TokenNumber, 11, 1, 0, "3"),
+				NewToken(TokenFloat, 11, 1, 0, "3"),
 				NewToken(TokenSlash, 12, 1, 0, "/"),
 				NewToken(TokenOpenParenthesis, 13, 1, 0, "("),
-				NewToken(TokenNumber, 14, 1, 0, "6"),
+				NewToken(TokenFloat, 14, 1, 0, "6"),
 				NewToken(TokenMinus, 15, 1, 0, "-"),
-				NewToken(TokenNumber, 16, 1, 0, "2"),
+				NewToken(TokenFloat, 16, 1, 0, "2"),
 				NewToken(TokenCloseParenthesis, 17, 1, 0, ")"),
 
 				NewToken(TokenMinus, 18, 1, 0, "-"),
 
-				NewToken(TokenNumber, 19, 2, 0, "10"),
+				NewToken(TokenFloat, 19, 2, 0, "10"),
 				NewToken(TokenSlash, 20, 1, 0, "/"),
-				NewToken(TokenNumber, 21, 1, 0, "2"),
+				NewToken(TokenFloat, 21, 1, 0, "2"),
 				NewToken(TokenEOF, 22, 0, 0, ""),
 			},
 			// (2 + 1) * 5 + 3 / (6 - 2)  -  10 / 2
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"_",
+						&ReferenceNode{"_", 0, 0},
 						&BinaryNode{
 							BinarySubtraction,
 							&BinaryNode{
@@ -182,17 +182,17 @@ func GetTokenTestData() map[string]TokenTestData {
 									BinaryMultiplication,
 									&BinaryNode{
 										BinaryAddition,
-										&NumberNode{
+										&FloatNode{
 											2,
 											0, 0,
 										},
-										&NumberNode{
+										&FloatNode{
 											1,
 											0, 0,
 										},
 										0, 0,
 									},
-									&NumberNode{
+									&FloatNode{
 										5,
 										0, 0,
 									},
@@ -200,17 +200,17 @@ func GetTokenTestData() map[string]TokenTestData {
 								},
 								&BinaryNode{
 									BinaryDivision,
-									&NumberNode{
+									&FloatNode{
 										3,
 										0, 0,
 									},
 									&BinaryNode{
 										BinarySubtraction,
-										&NumberNode{
+										&FloatNode{
 											6,
 											0, 0,
 										},
-										&NumberNode{
+										&FloatNode{
 											2,
 											0, 0,
 										},
@@ -222,11 +222,11 @@ func GetTokenTestData() map[string]TokenTestData {
 							},
 							&BinaryNode{
 								BinaryDivision,
-								&NumberNode{
+								&FloatNode{
 									10,
 									0, 0,
 								},
-								&NumberNode{
+								&FloatNode{
 									2,
 									0, 0,
 								},
@@ -245,22 +245,22 @@ func GetTokenTestData() map[string]TokenTestData {
 			[]Token{
 				NewToken(TokenName, 0, 1, 0, "_"),
 				NewToken(TokenAssign, 1, 1, 0, "="),
-				NewToken(TokenNumber, 2, 2, 0, "20"),
+				NewToken(TokenFloat, 2, 2, 0, "20"),
 				NewToken(TokenEquals, 4, 2, 0, "=="),
-				NewToken(TokenNumber, 6, 2, 0, "15"),
+				NewToken(TokenFloat, 6, 2, 0, "15"),
 				NewToken(TokenEOF, 8, 0, 0, ""),
 			},
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"_",
+						&ReferenceNode{"_", 0, 0},
 						&BinaryNode{
 							BinaryEquality,
-							&NumberNode{
+							&FloatNode{
 								20,
 								0, 0,
 							},
-							&NumberNode{
+							&FloatNode{
 								15,
 								0, 0,
 							},
@@ -278,11 +278,11 @@ func GetTokenTestData() map[string]TokenTestData {
 				NewToken(TokenIf, 0, 2, 0, "if"),
 				NewToken(TokenName, 2, 1, 0, "a"),
 				NewToken(TokenEquals, 3, 2, 0, "=="),
-				NewToken(TokenNumber, 5, 1, 0, "0"),
+				NewToken(TokenFloat, 5, 1, 0, "0"),
 				NewToken(TokenOpenBrace, 6, 1, 0, "{"),
 				NewToken(TokenName, 7, 1, 1, "b"),
 				NewToken(TokenAssign, 8, 1, 1, "="),
-				NewToken(TokenNumber, 9, 1, 1, "1"),
+				NewToken(TokenFloat, 9, 1, 1, "1"),
 				NewToken(TokenCloseBrace, 10, 1, 2, "}"),
 				NewToken(TokenEOF, 11, 0, 2, ""),
 			},
@@ -295,7 +295,7 @@ func GetTokenTestData() map[string]TokenTestData {
 								"a",
 								0, 0,
 							},
-							&NumberNode{
+							&FloatNode{
 								0,
 								0, 0,
 							},
@@ -304,8 +304,8 @@ func GetTokenTestData() map[string]TokenTestData {
 						do: &BlockNode{
 							[]Node{
 								&AssignNode{
-									"b",
-									&NumberNode{
+									&ReferenceNode{"b", 0, 0},
+									&FloatNode{
 										1,
 										0, 0,
 									},
@@ -325,17 +325,17 @@ func GetTokenTestData() map[string]TokenTestData {
 				NewToken(TokenIf, 0, 2, 0, "if"),
 				NewToken(TokenName, 2, 1, 0, "a"),
 				NewToken(TokenEquals, 3, 2, 0, "=="),
-				NewToken(TokenNumber, 5, 1, 0, "0"),
+				NewToken(TokenFloat, 5, 1, 0, "0"),
 				NewToken(TokenOpenBrace, 6, 1, 0, "{"),
 				NewToken(TokenName, 7, 1, 1, "b"),
 				NewToken(TokenAssign, 8, 1, 1, "="),
-				NewToken(TokenNumber, 9, 1, 1, "1"),
+				NewToken(TokenFloat, 9, 1, 1, "1"),
 				NewToken(TokenCloseBrace, 10, 1, 2, "}"),
 				NewToken(TokenElse, 11, 4, 2, "else"),
 				NewToken(TokenOpenBrace, 15, 1, 2, "{"),
 				NewToken(TokenName, 16, 1, 2, "b"),
 				NewToken(TokenAssign, 17, 1, 2, "="),
-				NewToken(TokenNumber, 18, 1, 2, "0"),
+				NewToken(TokenFloat, 18, 1, 2, "0"),
 				NewToken(TokenCloseBrace, 19, 1, 2, "}"),
 				NewToken(TokenEOF, 20, 0, 2, ""),
 			},
@@ -348,7 +348,7 @@ func GetTokenTestData() map[string]TokenTestData {
 								"a",
 								0, 0,
 							},
-							&NumberNode{
+							&FloatNode{
 								0,
 								0, 0,
 							},
@@ -357,8 +357,8 @@ func GetTokenTestData() map[string]TokenTestData {
 						do: &BlockNode{
 							[]Node{
 								&AssignNode{
-									"b",
-									&NumberNode{
+									&ReferenceNode{"b", 0, 0},
+									&FloatNode{
 										1,
 										0, 0,
 									},
@@ -371,8 +371,8 @@ func GetTokenTestData() map[string]TokenTestData {
 						otherwise: &BlockNode{
 							[]Node{
 								&AssignNode{
-									"b",
-									&NumberNode{
+									&ReferenceNode{"b", 0, 0},
+									&FloatNode{
 										0,
 										0, 0,
 									},
@@ -403,21 +403,22 @@ func GetTokenTestData() map[string]TokenTestData {
 				0, 0,
 			},
 		},
-		"lambda": { // a := func(a, b) { return a + b }
+		"lambda": { // a := fn(a: float, b: float) -> float { return a + b }
 			[]Token{
 				NewToken(TokenName, 0, 1, 0, "a"),
 				NewToken(TokenDeclare, 1, 2, 0, ":="),
-				NewToken(TokenFunc, 3, 4, 0, "func"),
-				NewToken(TokenOpenParenthesis, 7, 1, 0, "("),
-				NewToken(TokenName, 8, 1, 0, "a"),
-				NewToken(TokenColon, 9, 1, 0, ":"),
-				NewToken(TokenName, 10, 5, 0, "number"),
+				NewToken(TokenFunc, 3, 2, 0, "fn"),
+				NewToken(TokenOpenParenthesis, 5, 1, 0, "("),
+				NewToken(TokenName, 6, 1, 0, "a"),
+				NewToken(TokenColon, 6, 1, 0, ":"),
+				NewToken(TokenName, 10, 5, 0, "float"),
 				NewToken(TokenComma, 9, 1, 0, ","),
 				NewToken(TokenName, 10, 1, 0, "b"),
 				NewToken(TokenColon, 9, 1, 0, ":"),
-				NewToken(TokenName, 10, 5, 0, "number"),
+				NewToken(TokenName, 10, 5, 0, "float"),
 				NewToken(TokenCloseParenthesis, 11, 1, 0, ")"),
-				NewToken(TokenName, 10, 5, 0, "number"),
+				NewToken(TokenArrow, 12, 1, 0, "->"),
+				NewToken(TokenName, 10, 5, 0, "float"),
 
 				NewToken(TokenOpenBrace, 12, 1, 1, "{"),
 				NewToken(TokenReturn, 13, 6, 1, "return"),
@@ -431,20 +432,20 @@ func GetTokenTestData() map[string]TokenTestData {
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"a",
+						&ReferenceNode{"a", 0, 0},
 						&FunctionNode{
 							"*",
 							[]FunctionParameter{
 								{
 									"a",
-									&NumberSignature{},
+									&FloatSignature{},
 								},
 								{
 									"b",
-									&NumberSignature{},
+									&FloatSignature{},
 								},
 							},
-							&NumberSignature{},
+							&FloatSignature{},
 							&BlockNode{
 								[]Node{
 									&ReturnNode{
@@ -476,13 +477,19 @@ func GetTokenTestData() map[string]TokenTestData {
 		},
 		"function_declaration": {
 			[]Token{
-				NewToken(TokenFunc, 0, 4, 0, "func"),
+				NewToken(TokenFunc, 0, 2, 0, "fn"),
 				NewToken(TokenName, 4, 3, 0, "a"),
 				NewToken(TokenOpenParenthesis, 7, 1, 0, "("),
 				NewToken(TokenName, 8, 1, 0, "a"),
+				NewToken(TokenColon, 9, 1, 0, ":"),
+				NewToken(TokenName, 8, 1, 0, "float"),
 				NewToken(TokenComma, 9, 1, 0, ","),
 				NewToken(TokenName, 10, 1, 0, "b"),
+				NewToken(TokenColon, 9, 1, 0, ":"),
+				NewToken(TokenName, 8, 1, 0, "float"),
 				NewToken(TokenCloseParenthesis, 11, 1, 0, ")"),
+				NewToken(TokenArrow, 9, 1, 0, "->"),
+				NewToken(TokenName, 8, 1, 0, "float"),
 
 				NewToken(TokenOpenBrace, 12, 1, 1, "{"),
 				NewToken(TokenReturn, 13, 6, 1, "return"),
@@ -496,20 +503,20 @@ func GetTokenTestData() map[string]TokenTestData {
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"a",
+						&ReferenceNode{"a", 0, 0},
 						&FunctionNode{
 							"a",
 							[]FunctionParameter{
 								{
 									"a",
-									&NumberSignature{},
+									&FloatSignature{},
 								},
 								{
 									"b",
-									&NumberSignature{},
+									&FloatSignature{},
 								},
 							},
-							&NumberSignature{},
+							&FloatSignature{},
 							&BlockNode{
 								[]Node{
 									&ReturnNode{
@@ -552,7 +559,7 @@ func GetTokenTestData() map[string]TokenTestData {
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"p",
+						&ReferenceNode{"p", 0, 0},
 						&AccessNode{
 							&ReferenceNode{
 								"a",
@@ -577,7 +584,7 @@ func GetTokenTestData() map[string]TokenTestData {
 				NewToken(TokenName, 8, 1, 0, "a"),
 				NewToken(TokenComma, 11, 1, 0, ","),
 
-				NewToken(TokenNumber, 8, 1, 0, "3.141"),
+				NewToken(TokenFloat, 8, 1, 0, "3.141"),
 				NewToken(TokenComma, 11, 1, 0, ","),
 
 				NewToken(TokenString, 6, 1, 0, "\"Hello world!\""),
@@ -587,10 +594,10 @@ func GetTokenTestData() map[string]TokenTestData {
 				NewToken(TokenComma, 11, 1, 0, ","),
 
 				NewToken(TokenOpenBracket, 6, 1, 0, "["),
-				NewToken(TokenNumber, 6, 1, 0, "2"),
+				NewToken(TokenFloat, 6, 1, 0, "2"),
 				NewToken(TokenComma, 11, 1, 0, ","),
 
-				NewToken(TokenNumber, 6, 1, 0, "3"),
+				NewToken(TokenFloat, 6, 1, 0, "3"),
 				NewToken(TokenCloseBracket, 6, 1, 0, "]"),
 
 				NewToken(TokenCloseBracket, 6, 1, 0, "]"),
@@ -600,14 +607,14 @@ func GetTokenTestData() map[string]TokenTestData {
 			&BlockNode{
 				[]Node{
 					&AssignNode{
-						"data",
+						&ReferenceNode{"data", 0, 0},
 						&ListNode{
 							[]Node{
 								&ReferenceNode{
 									"a",
 									0, 0,
 								},
-								&NumberNode{
+								&FloatNode{
 									3.141,
 									0, 0,
 								},
@@ -622,10 +629,10 @@ func GetTokenTestData() map[string]TokenTestData {
 								},
 								&ListNode{
 									[]Node{
-										&NumberNode{
+										&FloatNode{
 											2,
 											0, 0,
-										}, &NumberNode{
+										}, &FloatNode{
 											3,
 											0, 0,
 										},
@@ -677,12 +684,20 @@ func NodeEquality(t *testing.T, n1 Node, n2 Node) {
 			t.Logf("String node quoted values match (%s)", n1.(*StringNode).value)
 		}
 
-	case NumberNodeType:
-		if n1.(*NumberNode).value != n2.(*NumberNode).value {
-			t.Errorf("Number node values don't match (%f and %f)", n1.(*NumberNode).value, n2.(*NumberNode).value)
+	case FloatNodeType:
+		if n1.(*FloatNode).value != n2.(*FloatNode).value {
+			t.Errorf("Float node values don't match (%f and %f)", n1.(*FloatNode).value, n2.(*FloatNode).value)
 		} else {
-			t.Logf("Number node values match (%f)", n1.(*NumberNode).value)
+			t.Logf("Float node values match (%f)", n1.(*FloatNode).value)
 		}
+
+	case IntegerNodeType:
+		if n1.(*IntegerNode).value.Cmp(n2.(*IntegerNode).value) != 0 {
+			t.Errorf("Integer node values don't match (%d and %d)", n1.(*IntegerNode).value, n2.(*IntegerNode).value)
+		} else {
+			t.Logf("Integer node values match (%d)", n1.(*IntegerNode).value)
+		}
+
 	case ReferenceNodeType:
 		if n1.(*ReferenceNode).name != n2.(*ReferenceNode).name {
 			t.Errorf("Reference node values don't match (%s and %s)", n1.(*ReferenceNode).name, n2.(*ReferenceNode).name)
@@ -734,11 +749,8 @@ func NodeEquality(t *testing.T, n1 Node, n2 Node) {
 		NodeEquality(t, n1.(*LoopNode).do, n2.(*LoopNode).do)
 
 	case AssignNodeType:
-		if n1.(*AssignNode).name != n2.(*AssignNode).name {
-			t.Errorf("Assigned value name is not the same (%s and %s)", n1.(*AssignNode).name, n2.(*AssignNode).name)
-		} else {
-			t.Logf("Assigned value name matches (%s)", n1.(*AssignNode).name)
-		}
+		t.Logf("Checking if value destination matches")
+		NodeEquality(t, n1.(*AssignNode).dest, n2.(*AssignNode).dest)
 
 		if n1.(*AssignNode).declare != n2.(*AssignNode).declare {
 			t.Errorf("Not same type of assigning (1: %v; 2: %v)", n1.(*AssignNode).declare, n2.(*AssignNode).declare)
@@ -747,22 +759,18 @@ func NodeEquality(t *testing.T, n1 Node, n2 Node) {
 		t.Logf("Checking equality of assignment values")
 		NodeEquality(t, n1.(*AssignNode).value, n2.(*AssignNode).value)
 
-	case CallNodeType:
-		n := n1.(*CallNode)
-		m := n2.(*CallNode)
+	case InvokeNodeType:
+		n := n1.(*InvokeNode)
+		m := n2.(*InvokeNode)
 
 		NodeEquality(t, n.source, m.source)
 
-		if n.keep == m.keep {
-			t.Logf("Call node keep modifier doesn't match (%v and %v)", n.keep, m.keep)
-		}
-
 		if len(n.args) != len(m.args) {
 			t.Fatalf("Call node arguments count does not match (%d and %d)", len(n.args), m.args)
 		}
 
 		for i, arg := range m.args {
-			NodeEquality(t, n1.(*CallNode).args[i], arg)
+			NodeEquality(t, n1.(*InvokeNode).args[i], arg)
 		}
 
 	case FunctionNodeType:
@@ -795,6 +803,37 @@ func NodeEquality(t *testing.T, n1 Node, n2 Node) {
 
 	case ReturnNodeType:
 		NodeEquality(t, n1.(*ReturnNode).value, n2.(*ReturnNode).value)
+
+	case AccessNodeType:
+		a1 := n1.(*AccessNode)
+		a2 := n2.(*AccessNode)
+
+		if a1.property != a2.property {
+			t.Errorf("Access node property does not match: .%s != .%s", a1.property, a2.property)
+		} else {
+			t.Logf("Access node property matches: .%s", a1.property)
+		}
+
+		NodeEquality(t, a1.source, a2.source)
+
+	case ListNodeType:
+		l1 := n1.(*ListNode)
+		l2 := n2.(*ListNode)
+
+		if l1.content == nil && l2.content == nil {
+			// fine
+			t.Logf("Both content types are yet to be determined")
+		} else if l1.content != nil || l2.content != nil {
+			t.Errorf("one is nil, one is not")
+		} else if !l1.content.Matches(l2.content) {
+			t.Errorf("signature doesn't match")
+		}
+
+		for i, v1 := range l1.items {
+			t.Logf("Checking item %d", i)
+			NodeEquality(t, v1, l2.items[i])
+		}
+
 	default:
 		panic("unimplemented node equality")
 	}
@@ -818,7 +857,7 @@ func SerializeTokens(tokens []Token) string {
 			out.WriteString("!")
 		case TokenSemicolon:
 			out.WriteString(";")
-		case TokenNumber:
+		case TokenFloat:
 			out.WriteString(token.Lexeme)
 		case TokenString:
 			out.WriteString(fmt.Sprintf("\"%s\"", token.Lexeme))
@@ -845,7 +884,7 @@ func SerializeTokens(tokens []Token) string {
 		case TokenNil:
 			out.WriteString("nil")
 		case TokenFunc:
-			out.WriteString("func")
+			out.WriteString("fn")
 		case TokenReturn:
 			out.WriteString("return ")
 		case TokenWhile:
@@ -904,10 +943,6 @@ func TestParser_Parse(t *testing.T) {
 	tokenData := GetTokenTestData()
 
 	for name, data := range tokenData {
-		if name != "empty_block" && name != "lambda" {
-			continue
-		}
-
 		t.Run(name, func(t *testing.T) {
 			t.Logf("Initializing parser")
 			p := NewParser("", []string{}, data.tokens)

core/stack.go

@@ -7,10 +7,10 @@ type Stack[T any] struct {
 	items []T
 }
 
-func NewStack[T any](capacity Pos) *Stack[T] {
+func NewStack[T any](maxCapacity Pos) *Stack[T] {
 	return &Stack[T]{
-		items:    make([]T, 16),
-		Capacity: capacity,
+		items:    make([]T, min(maxCapacity, 16)),
+		Capacity: maxCapacity,
 		Current:  0,
 	}
 }

core/stack_test.go

@@ -5,6 +5,30 @@ import (
 	"testing"
 )
 
+func CompareScope(t *testing.T, expectedScope []map[string]Value, actualScope *Scope) {
+	s := actualScope
+
+	for i := len(expectedScope) - 1; i >= 0; i-- {
+		if s == nil {
+			t.Fatal("scope cut unexpecetantly short")
+		}
+
+		for name, value := range expectedScope[i] {
+			v, ok := s.current[name]
+			if !ok {
+				t.Errorf("variable %s not found in correct scope", name)
+				continue
+			}
+
+			if !v.Equals(value) {
+				t.Errorf("variable %s has value %s but expected %s", name, v.String(), value.String())
+			} else {
+				t.Logf("variable %s has expected value %s", name, v.String())
+			}
+		}
+	}
+}
+
 func CompareStacks[T Value](t *testing.T, expected []T, actual *Stack[T]) {
 	if actual.Current != Pos(len(expected)) {
 		t.Errorf("Unexpected stack size. Expected %d, got %d", len(expected), actual.Current)

core/types.go

@@ -9,7 +9,8 @@ type Type int
 
 const (
 	TypeString Type = iota
-	TypeNumber
+	TypeInteger
+	TypeFloat
 	TypeBoolean
 	TypeNil
 	TypeList
@@ -24,8 +25,10 @@ func (t Type) String() string {
 	switch t {
 	case TypeString:
 		return "string"
-	case TypeNumber:
-		return "number"
+	case TypeInteger:
+		return "integer"
+	case TypeFloat:
+		return "float"
 	case TypeBoolean:
 		return "boolean"
 	case TypeNil:
@@ -51,8 +54,10 @@ func SignatureOf(v Value) TypeSignature {
 	switch t := v.(type) {
 	case *StringValue:
 		return &StringSignature{}
-	case *NumberValue:
-		return &NumberSignature{}
+	case *FloatValue:
+		return &FloatSignature{}
+	case *IntegerValue:
+		return &IntegerSignature{}
 	case *BoolValue:
 		return &BooleanSignature{}
 	case *ListValue:
@@ -138,22 +143,40 @@ func (*StringSignature) String() string {
 	return "string"
 }
 
-type NumberSignature struct{}
+type FloatSignature struct{}
 
-func (*NumberSignature) Type() Type {
-	return TypeNumber
+func (*FloatSignature) Type() Type {
+	return TypeFloat
 }
 
-func (s *NumberSignature) Matches(other TypeSignature) bool {
+func (s *FloatSignature) Matches(other TypeSignature) bool {
 	if other.Type() == TypeComposite {
 		return other.Matches(s)
 	}
 
-	return other.Type() == TypeAny || other.Type() == TypeNumber
+	return other.Type() == TypeAny || other.Type() == TypeFloat
 }
 
-func (*NumberSignature) String() string {
-	return "number"
+func (*FloatSignature) String() string {
+	return "float"
+}
+
+type IntegerSignature struct{}
+
+func (*IntegerSignature) Type() Type {
+	return TypeInteger
+}
+
+func (s *IntegerSignature) Matches(other TypeSignature) bool {
+	if other.Type() == TypeComposite {
+		return other.Matches(s)
+	}
+
+	return other.Type() == TypeAny || other.Type() == TypeInteger
+}
+
+func (*IntegerSignature) String() string {
+	return "int"
 }
 
 type BooleanSignature struct{}

core/values.go

@@ -3,7 +3,7 @@ package core
 import (
 	"errors"
 	"fmt"
-	"math"
+	"math/big"
 	"reflect"
 	"strconv"
 )
@@ -13,7 +13,8 @@ type ValueType int
 const (
 	NilValueType ValueType = iota
 	BoolValueType
-	NumberValueType
+	FloatValueType
+	IntegerValueType
 	StringValueType
 	ListValueType
 	ObjectValueType
@@ -30,8 +31,10 @@ func (v ValueType) String() string {
 		return "bool"
 	case ObjectValueType:
 		return "object"
-	case NumberValueType:
-		return "number"
+	case FloatValueType:
+		return "float"
+	case IntegerValueType:
+		return "int"
 	case StringValueType:
 		return "string"
 	case ListValueType:
@@ -57,11 +60,15 @@ func GoToValue(gov interface{}) Value {
 			v,
 		}
 	case int:
-		return &NumberValue{
-			float64(v),
+		return &IntegerValue{
+			new(big.Int).SetInt64(int64(v)),
+		}
+	case *big.Int:
+		return &IntegerValue{
+			v,
 		}
 	case float64:
-		return &NumberValue{
+		return &FloatValue{
 			v,
 		}
 	case string:
@@ -259,40 +266,71 @@ func (v *ObjectValue) Clone() Value {
 	}
 }
 
-// NumberValue Integer or floating-point values
-type NumberValue struct {
+// FloatValue floating-point values
+type FloatValue struct {
 	Number float64
 }
 
-const NumberSize int = 64
+const FloatSize int = 64
 
-func (v *NumberValue) Type() ValueType {
-	return NumberValueType
+func (v *FloatValue) Type() ValueType {
+	return FloatValueType
 }
 
-func (v *NumberValue) String() string {
-	return strconv.FormatFloat(v.Number, 'g', -1, NumberSize)
+func (v *FloatValue) String() string {
+	return strconv.FormatFloat(v.Number, 'g', -1, FloatSize)
 }
 
-func (v *NumberValue) DebugString() string {
+func (v *FloatValue) DebugString() string {
 	return v.String()
 }
 
-func (v *NumberValue) Equals(other Value) bool {
-	return other.Type() == NumberValueType && other.(*NumberValue).Number == v.Number
+func (v *FloatValue) Equals(other Value) bool {
+	return other.Type() == FloatValueType && other.(*FloatValue).Number == v.Number
 }
 
-func (v *NumberValue) Get(_ string) (Value, error) {
+func (v *FloatValue) Get(_ string) (Value, error) {
 	// TODO maybe add standard functions for number values?
 	return nil, errors.New("numbers have no properties")
 }
 
-func (v *NumberValue) Clone() Value {
-	return &NumberValue{
+func (v *FloatValue) Clone() Value {
+	return &FloatValue{
 		v.Number,
 	}
 }
 
+// IntegerValue whole number/integer values
+type IntegerValue struct {
+	Number *big.Int
+}
+
+func (v *IntegerValue) Type() ValueType {
+	return IntegerValueType
+}
+
+func (v *IntegerValue) String() string {
+	return v.Number.String()
+}
+
+func (v *IntegerValue) DebugString() string {
+	return v.String()
+}
+
+func (v *IntegerValue) Equals(other Value) bool {
+	return other.Type() == IntegerValueType && other.(*IntegerValue).Number.Cmp(v.Number) == 0
+}
+
+func (v *IntegerValue) Get(_ string) (Value, error) {
+	return nil, errors.New("numbers have no properties")
+}
+
+func (v *IntegerValue) Clone() Value {
+	return &IntegerValue{
+		new(big.Int).Set(v.Number),
+	}
+}
+
 type StringValue struct {
 	Text string
 }
@@ -348,7 +386,7 @@ var StringPrototype = map[string]*BuiltinFunctionValue{
 		Name: "length",
 		Signature: &FunctionSignature{
 			[]TypeSignature{},
-			&NumberSignature{},
+			&IntegerSignature{},
 		},
 		F: func(vm *VM, this Value, _ []Value) (Value, error) {
 			return GoToValue(len(this.(*StringValue).Text)), nil
@@ -357,11 +395,11 @@ var StringPrototype = map[string]*BuiltinFunctionValue{
 	"at": {
 		Name: "at",
 		Signature: &FunctionSignature{
-			[]TypeSignature{&NumberSignature{}},
+			[]TypeSignature{&IntegerSignature{}},
 			&StringSignature{},
 		},
 		F: func(vm *VM, this Value, args []Value) (Value, error) {
-			i := int(math.Floor(args[0].(*NumberValue).Number))
+			i := int(args[0].(*IntegerValue).Number.Int64())
 
 			if i < 0 || i >= len(this.(*StringValue).Text) {
 				return nil, errors.New("index is out of range")
@@ -450,13 +488,13 @@ var ListPrototype = map[string]*BuiltinFunctionValue{
 		"at",
 		&FunctionSignature{
 			[]TypeSignature{
-				&NumberSignature{},
+				&IntegerSignature{},
 			},
 			&InnerSignature{},
 		},
 		func(_ *VM, this Value, p []Value) (Value, error) {
 			items := this.(*ListValue).Items
-			index := int(p[0].(*NumberValue).Number)
+			index := int(p[0].(*IntegerValue).Number.Int64())
 
 			if index >= len(items) {
 				return nil, errors.New(fmt.Sprintf("list index %x out of range", index))
@@ -471,13 +509,13 @@ var ListPrototype = map[string]*BuiltinFunctionValue{
 		"put",
 		&FunctionSignature{
 			[]TypeSignature{
-				&NumberSignature{}, &InnerSignature{},
+				&FloatSignature{}, &InnerSignature{},
 			},
 			&NilSignature{},
 		},
 		func(_ *VM, this Value, args []Value) (Value, error) {
 			l := this.(*ListValue)
-			i := int(args[0].(*NumberValue).Number)
+			i := int(args[0].(*FloatValue).Number)
 			v := args[1]
 
 			// bounds check
@@ -496,7 +534,7 @@ var ListPrototype = map[string]*BuiltinFunctionValue{
 		"length",
 		&FunctionSignature{
 			[]TypeSignature{},
-			&NumberSignature{},
+			&IntegerSignature{},
 		},
 		func(_ *VM, this Value, _ []Value) (Value, error) {
 			return GoToValue(len(this.(*ListValue).Items)), nil
@@ -565,6 +603,7 @@ type FunctionValue struct {
 	Yield  TypeSignature
 	Chunk  *Chunk
 	Parent Value
+	Scope  *Scope
 }
 
 func (v *FunctionValue) Type() ValueType {
@@ -572,7 +611,7 @@ func (v *FunctionValue) Type() ValueType {
 }
 
 func (v *FunctionValue) String() string {
-	return fmt.Sprintf("<function name=%s>", v.Name)
+	return fmt.Sprintf("<function name=%s block=%p>", v.Name, v.Chunk)
 }
 
 func (v *FunctionValue) DebugString() string {
@@ -581,7 +620,6 @@ func (v *FunctionValue) DebugString() string {
 
 func (v *FunctionValue) Equals(other Value) bool {
 	return other.Type() == FunctionValueType &&
-		v.Name == other.(*FunctionValue).Name &&
 		v.Chunk == other.(*FunctionValue).Chunk
 }
 
@@ -596,6 +634,7 @@ func (v *FunctionValue) Clone() Value {
 		v.Yield,
 		v.Chunk,
 		v.Parent,
+		v.Scope,
 	}
 }
 
@@ -637,43 +676,3 @@ func (v *BuiltinFunctionValue) Clone() Value {
 		v.Constant,
 	}
 }
-
-// VariableValue a value wrapper for variables kept on the stack
-type VariableValue struct {
-	name  string
-	value Value
-	scope Pos
-}
-
-func (v *VariableValue) Type() ValueType {
-	return VariableValueType
-}
-
-func (v *VariableValue) String() string {
-	return fmt.Sprintf("<variable name=%s value=%s scope=%d>", v.name, v.value, v.scope)
-
-	// variables should not be accessed on the stack; normal values should be pushed and popped predictably
-	//panic("tried getting string value of a unreachable value")
-}
-
-func (v *VariableValue) DebugString() string {
-	return v.String()
-}
-
-func (v *VariableValue) Equals(other Value) bool {
-	return other.Type() == VariableValueType &&
-		v.name == other.(*VariableValue).name &&
-		v.value.Equals(other.(*VariableValue).value)
-}
-
-func (v *VariableValue) Get(_ string) (Value, error) {
-	return nil, errors.New("variables have no properties")
-}
-
-func (v *VariableValue) Clone() Value {
-	return &VariableValue{
-		v.name,
-		v.value.Clone(),
-		v.scope,
-	}
-}

core/values_test.go

@@ -21,15 +21,21 @@ func CompareValues(t *testing.T, got Value, want Value) {
 		} else {
 			t.Logf("Both are same boolean (%s)", want.(*BoolValue).String())
 		}
-	case NumberValueType:
-		if got.(*NumberValue).Number != want.(*NumberValue).Number {
-			t.Errorf("number value mismatch: got %v, want %v", got.(*NumberValue), want.(*NumberValue))
+	case FloatValueType:
+		if got.(*FloatValue).Number != want.(*FloatValue).Number {
+			t.Errorf("number value mismatch: got %v, want %v", got.(*FloatValue), want.(*FloatValue))
 		} else {
-			t.Logf("Both are same number (%s)", got.(*NumberValue).String())
+			t.Logf("Both are same number (%s)", got.(*FloatValue).String())
+		}
+	case IntegerValueType:
+		if got.(*IntegerValue).Number.String() != want.(*IntegerValue).Number.String() {
+			t.Errorf("number value mismatch: got %v, want %v", got.(*IntegerValue), want.(*IntegerValue))
+		} else {
+			t.Logf("Both are same number (%s)", got.(*IntegerValue).String())
 		}
 	case StringValueType:
 		if got.(*StringValue).Text != want.(*StringValue).Text {
-			t.Errorf("string value mismatch: got %v, want %v", got.(*StringValue), want.(*StringValue))
+			t.Errorf("string value mismatch: got %s, want %s", got.(*StringValue), want.(*StringValue))
 		} else {
 			t.Logf("Both are same string (%s)", got.(*StringValue).String())
 		}
@@ -64,20 +70,6 @@ func CompareValues(t *testing.T, got Value, want Value) {
 			t.Errorf("builtin function parameter count mismatch: got %v, want %v", n, m)
 		}
 
-	case VariableValueType:
-		n := got.(*VariableValue)
-		m := want.(*VariableValue)
-
-		if n.name != m.name {
-			t.Errorf("variable name mismatch: got %v, want %v", n.name, m.name)
-		}
-
-		if n.scope != m.scope {
-			t.Errorf("variable scope mismatch: got %v, want %v", n.scope, m.scope)
-		}
-
-		CompareValues(t, n.value, m.value)
-
 	case ListValueType:
 		n := got.(*ListValue)
 		m := want.(*ListValue)

core/vm.go

@@ -7,7 +7,9 @@ import (
 	"fmt"
 	"log"
 	"math"
+	"math/big"
 	"os"
+	"strconv"
 	"strings"
 )
 
@@ -20,30 +22,52 @@ const (
 	// InstructionPop pop and delete the first item on the stack
 	InstructionPop
 
-	// InstructionAdd pop two and add them
-	InstructionAdd
-	// InstructionSub pop two and subtract the second from the first
-	InstructionSub
-	// InstructionMul pop two and multiply them
-	InstructionMul
-	// InstructionDiv pop two and divide the second by the first
-	InstructionDiv
-	// InstructionNegate negate the value; if it was positive, make it negative, and vice versa.
-	InstructionNegate
+	// InstructionAddFloat pop two floats and add them
+	InstructionAddFloat
+	// InstructionSubFloat pop two floats and subtract the second from the first
+	InstructionSubFloat
+	// InstructionMulFloat pop two floats and multiply them
+	InstructionMulFloat
+	// InstructionDivFloat pop two floats and divide the second by the first
+	InstructionDivFloat
+	// InstructionNegateFloat negate the float; if it was positive, make it negative, and vice versa.
+	InstructionNegateFloat
+
+	// InstructionAddInt pop two ints and add them
+	InstructionAddInt
+	// InstructionSubInt pop two ints and subtract the second from the first
+	InstructionSubInt
+	// InstructionMulInt pop two ints and multiply them
+	InstructionMulInt
+	// InstructionDivInt pop two ints and divide the second by the first
+	InstructionDivInt
+	// InstructionNegateInt negate the int; if it was positive, make it negative, and vice versa.
+	InstructionNegateInt
+
 	// InstructionEquals whether the two top values on the stack are equal
 	InstructionEquals
 	// InstructionNotEqual whether the two top values on the stack are not equal
 	InstructionNotEqual
 	// InstructionNot inverts boolean (true => false, false => true)
 	InstructionNot
-	// InstructionLess pops two from stack, pushes whether the lowest is less than the highest
-	InstructionLess
-	// InstructionLessOrEqual pops two from stack, pushes whether the lowest is less or equal than the highest
-	InstructionLessOrEqual
-	// InstructionGreater pops two from stack, pushes whether the lowest is greater than the highest
-	InstructionGreater
-	// InstructionGreaterOrEqual pops two from stack, pushes whether the lowest is greater or equal than the highest
-	InstructionGreaterOrEqual
+
+	// InstructionLessFloat pops two from stack, pushes whether the lowest is less than the highest
+	InstructionLessFloat
+	// InstructionLessOrEqualFloat pops two from stack, pushes whether the lowest is less or equal than the highest
+	InstructionLessOrEqualFloat
+	// InstructionGreaterFloat pops two from stack, pushes whether the lowest is greater than the highest
+	InstructionGreaterFloat
+	// InstructionGreaterOrEqualFloat pops two from stack, pushes whether the lowest is greater or equal than the highest
+	InstructionGreaterOrEqualFloat
+
+	// InstructionLessInt pops two from stack, pushes whether the lowest is less than the highest
+	InstructionLessInt
+	// InstructionLessOrEqualInt pops two from stack, pushes whether the lowest is less or equal than the highest
+	InstructionLessOrEqualInt
+	// InstructionGreaterInt pops two from stack, pushes whether the lowest is greater than the highest
+	InstructionGreaterInt
+	// InstructionGreaterOrEqualInt pops two from stack, pushes whether the lowest is greater or equal than the highest
+	InstructionGreaterOrEqualInt
 
 	// InstructionAccessProperty gets a property from a value, and pops it onto the stack
 	InstructionAccessProperty
@@ -80,6 +104,8 @@ const (
 
 	// InstructionSwap swap the two top items on the stack (1, 2 -> 2, 1)
 	InstructionSwap
+	// InstructionDuplicate push a copy of the item on top of the stack (1 -> 1, 1)
+	InstructionDuplicate
 
 	// InstructionAnd pop two booleans and push true if both are true
 	InstructionAnd
@@ -116,30 +142,48 @@ func (b Bytecode) String() string {
 		return "RETURN"
 	case InstructionPop:
 		return "POP"
-	case InstructionAdd:
-		return "ADD"
-	case InstructionSub:
-		return "SUB"
-	case InstructionMul:
-		return "MUL"
-	case InstructionDiv:
-		return "DIV"
-	case InstructionNegate:
-		return "NEGATE"
+	case InstructionAddFloat:
+		return "ADD_FLOAT"
+	case InstructionSubFloat:
+		return "SUB_FLOAT"
+	case InstructionMulFloat:
+		return "MUL_FLOAT"
+	case InstructionDivFloat:
+		return "DIV_FLOAT"
+	case InstructionNegateFloat:
+		return "NEGATE_FLOAT"
+	case InstructionAddInt:
+		return "ADD_INT"
+	case InstructionSubInt:
+		return "SUB_INT"
+	case InstructionMulInt:
+		return "MUL_INT"
+	case InstructionDivInt:
+		return "DIV_INT"
+	case InstructionNegateInt:
+		return "NEGATE_INT"
 	case InstructionEquals:
 		return "EQUALS"
 	case InstructionNotEqual:
 		return "NOT_EQUALS"
 	case InstructionNot:
 		return "NOT"
-	case InstructionLess:
-		return "LESS"
-	case InstructionLessOrEqual:
-		return "LESS_OR_EQUAL"
-	case InstructionGreater:
-		return "GREATER_OR_EQUAL"
-	case InstructionGreaterOrEqual:
-		return "GREATER_OR_EQUAL"
+	case InstructionLessFloat:
+		return "LESS_FLOAT"
+	case InstructionLessOrEqualFloat:
+		return "LESS_OR_EQUAL_FLOAT"
+	case InstructionGreaterFloat:
+		return "GREATER_FLOAT"
+	case InstructionGreaterOrEqualFloat:
+		return "GREATER_OR_EQUAL_FLOAT"
+	case InstructionLessInt:
+		return "LESS_INT"
+	case InstructionLessOrEqualInt:
+		return "LESS_OR_EQUAL_INT"
+	case InstructionGreaterInt:
+		return "GREATER_INT"
+	case InstructionGreaterOrEqualInt:
+		return "GREATER_OR_EQUAL_INT"
 	case InstructionJump:
 		return "JUMP"
 	case InstructionJumpFalse:
@@ -192,6 +236,8 @@ func (b Bytecode) String() string {
 		return "ACCESS_PROPERTY"
 	case InstructionConcatLists:
 		return "CONCAT_LISTS"
+	case InstructionDuplicate:
+		return "DUPLICATE"
 	}
 	return "UNDEFINED"
 }
@@ -225,6 +271,30 @@ func (c Chunk) String() string {
 	return b.String()
 }
 
+func (c *Chunk) Equals(other *Chunk) bool {
+	if len(c.Bytecode) != len(other.Bytecode) {
+		return false
+	}
+
+	for i, bc := range c.Bytecode {
+		if other.Bytecode[i] != bc {
+			return false
+		}
+	}
+
+	if len(c.Constants) != len(other.Constants) {
+		return false
+	}
+
+	for i := 0; i < len(c.Constants); i++ {
+		if other.Constants[i] != c.Constants[i] {
+			return false
+		}
+	}
+
+	return true
+}
+
 func NewChunk(bytecode []Bytecode, constants []Value) *Chunk {
 	return &Chunk{bytecode, constants}
 }
@@ -232,7 +302,7 @@ func NewChunk(bytecode []Bytecode, constants []Value) *Chunk {
 func RegisterGOBTypes() {
 	gob.Register(&StringValue{""})
 	gob.Register(&BoolValue{false})
-	gob.Register(&NumberValue{0})
+	gob.Register(&FloatValue{0})
 	gob.Register(&FunctionValue{
 		Name:   "",
 		Params: nil,
@@ -241,7 +311,7 @@ func RegisterGOBTypes() {
 
 	// Signatures
 	gob.Register(&NilSignature{})
-	gob.Register(&NumberSignature{})
+	gob.Register(&FloatSignature{})
 	gob.Register(&StringSignature{})
 	gob.Register(&FunctionSignature{})
 	gob.Register(&ListSignature{})
@@ -286,26 +356,29 @@ type VM struct {
 
 	// instruction pointer
 	ip Pos
-	scope Pos
 
 	// global variable storage
 	globals map[string]Value
-	variableEnd Pos
+	// local variable storage
+	scope *Scope
 
-	stack *Stack[Value]
+	Stack *Stack[Value]
 	call  *Stack[Call]
 }
 
+type Scope struct {
+	current map[string]Value
+	parent  *Scope
+}
+
 type Call struct {
 	chunk *Chunk
 	ip    Pos
-	stackEnd    Pos
-	variableEnd Pos
-	scope       Pos
+	scope *Scope
 }
 
 var DefaultGlobals = map[string]Value{
-	"write": &BuiltinFunctionValue{
+	"println": &BuiltinFunctionValue{
 		"write", // always remember where you come from...
 		&FunctionSignature{
 			[]TypeSignature{&AnySignature{}},
@@ -313,7 +386,7 @@ var DefaultGlobals = map[string]Value{
 		},
 		func(_ *VM, this Value, v []Value) (Value, error) {
 			println(v[0].String())
-			return nil, nil
+			return &NilValue{}, nil
 		},
 		nil,
 		false,
@@ -326,7 +399,7 @@ var DefaultGlobals = map[string]Value{
 		},
 		func(_ *VM, this Value, v []Value) (Value, error) {
 			print(v[0].String())
-			return nil, nil
+			return &NilValue{}, nil
 		},
 		nil,
 		false,
@@ -368,12 +441,12 @@ var DefaultGlobals = map[string]Value{
 	"char": &BuiltinFunctionValue{
 		"char",
 		&FunctionSignature{
-			[]TypeSignature{&NumberSignature{}},
+			[]TypeSignature{&IntegerSignature{}},
 			&StringSignature{},
 		},
 		func(vm *VM, this Value, args []Value) (Value, error) {
-			n := args[0].(*NumberValue).Number
-			b := byte(n)
+			n := args[0].(*IntegerValue).Number
+			b := n.Bytes()[0]
 
 			return &StringValue{
 				string([]byte{b}),
@@ -383,16 +456,16 @@ var DefaultGlobals = map[string]Value{
 		true,
 	},
 	"byte": &BuiltinFunctionValue{
-		"char",
+		"byte",
 		&FunctionSignature{
 			[]TypeSignature{&StringSignature{}},
-			&NumberSignature{},
+			&IntegerSignature{},
 		},
 		func(vm *VM, this Value, args []Value) (Value, error) {
 			s := args[0].(*StringValue).Text
-			b := []byte(s)[0]
+			n := new(big.Int).SetBytes([]byte(s))
 
-			return &NumberValue{float64(b)}, nil
+			return &IntegerValue{n}, nil
 		},
 		nil,
 		true,
@@ -453,6 +526,66 @@ var DefaultGlobals = map[string]Value{
 		nil,
 		true,
 	},
+	"int": &BuiltinFunctionValue{
+		"int",
+		&FunctionSignature{
+			[]TypeSignature{&AnySignature{}},
+			&CompositeSignature{
+				&IntegerSignature{},
+				&NilSignature{},
+			},
+		},
+		func(vm *VM, _ Value, args []Value) (Value, error) {
+			switch v := args[0].(type) {
+			case *IntegerValue:
+				return &IntegerValue{v.Number}, nil // this might need to clone the value instead
+			case *FloatValue:
+				n := new(big.Int).SetInt64(int64(v.Number))
+				return &IntegerValue{n}, nil
+			case *StringValue:
+				n, success := new(big.Int).SetString(v.Text, 0) // determine base
+				if !success {
+					return &NilValue{}, nil
+				}
+
+				return &IntegerValue{n}, nil
+			default:
+				return nil, errors.New(fmt.Sprintf("%s cannot become an integer", v))
+			}
+		},
+		nil,
+		true,
+	},
+	"float": &BuiltinFunctionValue{
+		"float",
+		&FunctionSignature{
+			[]TypeSignature{&AnySignature{}},
+			&CompositeSignature{
+				&FloatSignature{},
+				&NilSignature{},
+			},
+		},
+		func(vm *VM, _ Value, args []Value) (Value, error) {
+			switch v := args[0].(type) {
+			case *IntegerValue:
+				n, _ := v.Number.Float64()
+				return &FloatValue{n}, nil // this might need to clone the value instead
+			case *FloatValue:
+				return &FloatValue{v.Number}, nil
+			case *StringValue:
+				num, err := strconv.ParseFloat(v.Text, FloatSize)
+				if err != nil {
+					return &NilValue{}, nil
+				}
+
+				return &FloatValue{num}, nil
+			default:
+				return nil, errors.New(fmt.Sprintf("%s cannot become an integer", v))
+			}
+		},
+		nil,
+		true,
+	},
 	"type": &BuiltinFunctionValue{
 		Name: "type",
 		Signature: &FunctionSignature{
@@ -470,11 +603,11 @@ var DefaultGlobals = map[string]Value{
 	"exit": &BuiltinFunctionValue{
 		"exit",
 		&FunctionSignature{
-			[]TypeSignature{&NumberSignature{}},
+			[]TypeSignature{&FloatSignature{}},
 			&NilSignature{},
 		},
 		func(vm *VM, this Value, args []Value) (Value, error) {
-			os.Exit(int(args[0].(*NumberValue).Number))
+			os.Exit(int(args[0].(*FloatValue).Number))
 			return &NilValue{}, nil
 		},
 		nil,
@@ -483,11 +616,11 @@ var DefaultGlobals = map[string]Value{
 	"floor": &BuiltinFunctionValue{
 		"floor",
 		&FunctionSignature{
-			[]TypeSignature{&NumberSignature{}},
-			&NumberSignature{},
+			[]TypeSignature{&FloatSignature{}},
+			&FloatSignature{},
 		},
 		func(vm *VM, this Value, args []Value) (Value, error) {
-			return &NumberValue{math.Floor(args[0].(*NumberValue).Number)}, nil
+			return &FloatValue{math.Floor(args[0].(*FloatValue).Number)}, nil
 		},
 		nil,
 		true,
@@ -495,11 +628,11 @@ var DefaultGlobals = map[string]Value{
 	"ceil": &BuiltinFunctionValue{
 		"ceil",
 		&FunctionSignature{
-			[]TypeSignature{&NumberSignature{}},
-			&NumberSignature{},
+			[]TypeSignature{&FloatSignature{}},
+			&FloatSignature{},
 		},
 		func(vm *VM, this Value, args []Value) (Value, error) {
-			return &NumberValue{math.Ceil(args[0].(*NumberValue).Number)}, nil
+			return &FloatValue{math.Ceil(args[0].(*FloatValue).Number)}, nil
 		},
 		nil,
 		true,
@@ -507,14 +640,14 @@ var DefaultGlobals = map[string]Value{
 	"roundd": &BuiltinFunctionValue{
 		"roundd",
 		&FunctionSignature{
-			[]TypeSignature{&NumberSignature{}, &NumberSignature{}},
-			&NumberSignature{},
+			[]TypeSignature{&FloatSignature{}, &FloatSignature{}},
+			&FloatSignature{},
 		},
 		func(vm *VM, this Value, args []Value) (Value, error) {
-			x := args[0].(*NumberValue).Number
-			decimals := args[1].(*NumberValue).Number
+			x := args[0].(*FloatValue).Number
+			decimals := args[1].(*FloatValue).Number
 			multiplier := math.Pow(10, decimals)
-			return &NumberValue{math.Round(x*multiplier) / multiplier}, nil
+			return &FloatValue{math.Round(x*multiplier) / multiplier}, nil
 		},
 		nil,
 		true,
@@ -524,10 +657,13 @@ var DefaultGlobals = map[string]Value{
 func NewVM(chunk *Chunk, stackSize Pos, callstackSize Pos) *VM {
 	vm := &VM{
 		chunk: chunk,
-		stack: NewStack[Value](stackSize),
+		Stack: NewStack[Value](stackSize),
 		call:  NewStack[Call](callstackSize),
 
 		globals: DefaultGlobals,
+		scope: &Scope{
+			current: map[string]Value{},
+		},
 	}
 
 	return vm
@@ -544,141 +680,190 @@ func (vm *VM) Next() bool {
 	case InstructionReturn:
 		if vm.call.Current == 0 {
 			return false
-		} else {
-			v := vm.stack.Pop()
+		}
+
+		v := vm.Stack.Pop()
 		c := vm.call.Pop()
 
 		// reset stack current and variable end and scope
-			vm.variableEnd = c.variableEnd
-			vm.stack.Current = c.stackEnd
 		vm.scope = c.scope
 
 		// reset to calling position
 		vm.ip = c.ip
 		vm.chunk = c.chunk
 
-			vm.purgeVars()
-
-			vm.stack.Push(v)
-		}
+		vm.Stack.Push(v)
 
 	case InstructionPop:
-		vm.stack.Pop()
+		vm.Stack.Pop()
 
 	case InstructionConstant:
-		vm.stack.Push(vm.ReadConstant())
+		c := vm.ReadConstant()
 
-	case InstructionAdd:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+		if c, ok := c.(*FunctionValue); ok {
+			c.Scope = vm.scope
+		}
 
-		vm.stack.Push(&NumberValue{l + r})
+		vm.Stack.Push(c)
 
-	case InstructionSub:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+	case InstructionAddFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&NumberValue{l - r})
+		vm.Stack.Push(&FloatValue{l + r})
 
-	case InstructionMul:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+	case InstructionSubFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&NumberValue{l * r})
+		vm.Stack.Push(&FloatValue{l - r})
 
-	case InstructionDiv:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+	case InstructionMulFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&NumberValue{l / r})
+		vm.Stack.Push(&FloatValue{l * r})
 
-	case InstructionNegate:
-		v := vm.stack.Pop().(*NumberValue).Number
+	case InstructionDivFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&NumberValue{-v})
+		vm.Stack.Push(&FloatValue{l / r})
+
+	case InstructionNegateFloat:
+		v := vm.Stack.Pop().(*FloatValue).Number
+
+		vm.Stack.Push(&FloatValue{-v})
+
+	case InstructionAddInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&IntegerValue{new(big.Int).Add(l, r)})
+
+	case InstructionSubInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&IntegerValue{new(big.Int).Sub(l, r)})
+
+	case InstructionMulInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&IntegerValue{new(big.Int).Mul(l, r)})
+
+	case InstructionDivInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&IntegerValue{new(big.Int).Div(l, r)})
+
+	case InstructionNegateInt:
+		v := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&IntegerValue{new(big.Int).Neg(v)})
 
 	case InstructionEquals:
-		vm.stack.Push(
-			&BoolValue{vm.stack.Pop().Equals(vm.stack.Pop())},
+		vm.Stack.Push(
+			&BoolValue{vm.Stack.Pop().Equals(vm.Stack.Pop())},
 		)
 
 	case InstructionNotEqual:
-		vm.stack.Push(
-			&BoolValue{!vm.stack.Pop().Equals(vm.stack.Pop())},
+		vm.Stack.Push(
+			&BoolValue{!vm.Stack.Pop().Equals(vm.Stack.Pop())},
 		)
 
 	case InstructionNot:
-		b := vm.stack.Pop().(*BoolValue).Boolean
-		vm.stack.Push(&BoolValue{!b})
+		b := vm.Stack.Pop().(*BoolValue).Boolean
+		vm.Stack.Push(&BoolValue{!b})
 
 	case InstructionAnd:
-		r := vm.stack.Pop().(*BoolValue).Boolean
-		l := vm.stack.Pop().(*BoolValue).Boolean
-		vm.stack.Push(&BoolValue{l && r})
+		r := vm.Stack.Pop().(*BoolValue).Boolean
+		l := vm.Stack.Pop().(*BoolValue).Boolean
+		vm.Stack.Push(&BoolValue{l && r})
 
 	case InstructionOr:
-		r := vm.stack.Pop().(*BoolValue).Boolean
-		l := vm.stack.Pop().(*BoolValue).Boolean
-		vm.stack.Push(&BoolValue{l || r})
+		r := vm.Stack.Pop().(*BoolValue).Boolean
+		l := vm.Stack.Pop().(*BoolValue).Boolean
+		vm.Stack.Push(&BoolValue{l || r})
 
-	case InstructionLess:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+	case InstructionLessFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&BoolValue{l < r})
+		vm.Stack.Push(&BoolValue{l < r})
 
-	case InstructionLessOrEqual:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+	case InstructionLessOrEqualFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&BoolValue{l <= r})
+		vm.Stack.Push(&BoolValue{l <= r})
 
-	case InstructionGreater:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+	case InstructionGreaterFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&BoolValue{l > r})
+		vm.Stack.Push(&BoolValue{l > r})
 
-	case InstructionGreaterOrEqual:
-		r := vm.stack.Pop().(*NumberValue).Number
-		l := vm.stack.Pop().(*NumberValue).Number
+	case InstructionGreaterOrEqualFloat:
+		r := vm.Stack.Pop().(*FloatValue).Number
+		l := vm.Stack.Pop().(*FloatValue).Number
 
-		vm.stack.Push(&BoolValue{l >= r})
+		vm.Stack.Push(&BoolValue{l >= r})
+
+	case InstructionLessInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&BoolValue{l.Cmp(r) == -1})
+
+	case InstructionLessOrEqualInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&BoolValue{l.Cmp(r) != 1})
+
+	case InstructionGreaterInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&BoolValue{l.Cmp(r) == 1})
+
+	case InstructionGreaterOrEqualInt:
+		r := vm.Stack.Pop().(*IntegerValue).Number
+		l := vm.Stack.Pop().(*IntegerValue).Number
+
+		vm.Stack.Push(&BoolValue{l.Cmp(r) != -1})
 
 	case InstructionCall:
-		v := vm.stack.Pop()
+		v := vm.Stack.Pop()
 		switch f := v.(type) {
 		case *FunctionValue:
 			vm.call.Push(Call{
 				chunk: vm.chunk,
 				ip:    vm.ip,
-				stackEnd:    vm.stack.Current - Pos(len(f.Params)),
-				variableEnd: vm.variableEnd,
 				scope: vm.scope,
 			})
 
+			vm.scope = f.Scope
+			vm.descend()
+
 			for i := len(f.Params) - 1; i >= 0; i-- {
-				p := vm.stack.Current - Pos(len(f.Params)) + Pos(i)
-				vm.stack.items[p] = &VariableValue{
-					f.Params[i].Name,
-					vm.stack.items[p],
-					vm.scope,
-				}
+				vm.addVar(f.Params[i].Name, vm.Stack.Pop())
 			}
 
 			if f.Parent != nil {
 				vm.addVar("this", f.Parent)
 			}
 
-			vm.variableEnd = vm.stack.Current
-
 			vm.chunk = f.Chunk
 			vm.ip = 0
 		case *BuiltinFunctionValue:
 			args := make([]Value, len(f.Signature.In))
 
 			for i := len(f.Signature.In) - 1; i >= 0; i-- {
-				args[i] = vm.stack.Pop()
+				args[i] = vm.Stack.Pop()
 			}
 
 			v, err := f.F(vm, f.Parent, args)
@@ -686,9 +871,13 @@ func (vm *VM) Next() bool {
 				vm.error(err.Error())
 			}
 
-			vm.stack.Push(v)
+			if v == nil {
+				v = &NilValue{}
+			}
+
+			vm.Stack.Push(v)
 		default:
-			vm.error(fmt.Sprintf("value called is not a function (%s, type %T)", v.DebugString(), v))
+			vm.error(fmt.Sprintf("%s (%s) is not callable ", v.DebugString(), v.Type()))
 			return false
 		}
 
@@ -700,7 +889,7 @@ func (vm *VM) Next() bool {
 
 	case InstructionJumpFalse:
 		n := vm.NextU16()
-		if !vm.stack.Pop().(*BoolValue).Boolean {
+		if !vm.Stack.Pop().(*BoolValue).Boolean {
 			vm.ip += Pos(n)
 		}
 
@@ -713,67 +902,61 @@ func (vm *VM) Next() bool {
 			return false
 		}
 
-		vm.stack.Push(v.value)
+		vm.Stack.Push(v)
 
 	case InstructionSetLocal:
-		value := vm.stack.Pop().(Value)
+		value := vm.Stack.Peek().Clone()
 		name := vm.GetConstant(vm.NextByte()).(*StringValue).Text
 
-		v := vm.getVar(name)
-
-		if v == nil {
-			vm.error(fmt.Sprintf("cannot set local: undefined variable %s", name))
-		}
-
-		v.value = value.Clone()
+		vm.setVar(name, value)
 
 	case InstructionDeclareLocal:
 		vm.addVar(
 			vm.GetConstant(vm.NextByte()).(*StringValue).Text,
-			vm.stack.Pop().Clone(),
+			vm.Stack.Peek().Clone(),
 		)
 
 	case InstructionGetGlobal:
-		vm.stack.Push(vm.globals[vm.GetConstant(vm.NextByte()).(*StringValue).Text])
+		vm.Stack.Push(vm.globals[vm.GetConstant(vm.NextByte()).(*StringValue).Text])
 
 	case InstructionSetGlobal:
-		vm.globals[vm.GetConstant(vm.NextByte()).(*StringValue).Text] = vm.stack.Pop()
+		vm.globals[vm.GetConstant(vm.NextByte()).(*StringValue).Text] = vm.Stack.Pop()
 
 	case InstructionTrue:
-		vm.stack.Push(&BoolValue{true})
+		vm.Stack.Push(&BoolValue{true})
 
 	case InstructionFalse:
-		vm.stack.Push(&BoolValue{false})
+		vm.Stack.Push(&BoolValue{false})
 
 	case InstructionNil:
-		vm.stack.Push(&NilValue{})
+		vm.Stack.Push(&NilValue{})
 
 	case InstructionFormList:
 		n := int(vm.NextU16())
 
 		items := make([]Value, n)
 		for i := n - 1; i >= 0; i-- {
-			items[i] = vm.stack.Pop()
+			items[i] = vm.Stack.Pop()
 		}
 
-		vm.stack.Push(&ListValue{
+		vm.Stack.Push(&ListValue{
 			items,
 		})
 
 	case InstructionNewList:
-		vm.stack.Push(&ListValue{[]Value{}})
+		vm.Stack.Push(&ListValue{[]Value{}})
 
 	case InstructionAppend:
-		value := vm.stack.Pop()
-		list := vm.stack.Pop().(*ListValue)
+		value := vm.Stack.Pop()
+		list := vm.Stack.Pop().(*ListValue)
 		list.Items = append(list.Items, value)
-		vm.stack.Push(list)
+		vm.Stack.Push(list)
 
 	case InstructionConcatLists:
-		r := vm.stack.Pop().(*ListValue)
-		l := vm.stack.Pop().(*ListValue)
+		r := vm.Stack.Pop().(*ListValue)
+		l := vm.Stack.Pop().(*ListValue)
 
-		vm.stack.Push(&ListValue{
+		vm.Stack.Push(&ListValue{
 			append(l.Items, r.Items...),
 		})
 
@@ -784,23 +967,26 @@ func (vm *VM) Next() bool {
 		vm.ascend()
 
 	case InstructionStringConversion:
-		v := vm.stack.Pop()
-		vm.stack.Push(&StringValue{v.String()})
+		v := vm.Stack.Pop()
+		vm.Stack.Push(&StringValue{v.String()})
 
 	case InstructionStringConcatenation:
-		r := vm.stack.Pop().(*StringValue).Text
-		l := vm.stack.Pop().(*StringValue).Text
+		r := vm.Stack.Pop().(*StringValue).Text
+		l := vm.Stack.Pop().(*StringValue).Text
 
-		vm.stack.Push(&StringValue{l + r})
+		vm.Stack.Push(&StringValue{l + r})
 
 	case InstructionSwap:
-		r := vm.stack.Pop()
-		l := vm.stack.Pop()
+		r := vm.Stack.Pop()
+		l := vm.Stack.Pop()
 
-		vm.stack.Push(r, l)
+		vm.Stack.Push(r, l)
+
+	case InstructionDuplicate:
+		vm.Stack.Push(vm.Stack.Peek().Clone())
 
 	case InstructionAccessProperty:
-		source := vm.stack.Pop()
+		source := vm.Stack.Pop()
 		property := vm.ReadConstant()
 
 		member, err := source.Get(property.(*StringValue).String())
@@ -815,9 +1001,19 @@ func (vm *VM) Next() bool {
 			member.(*BuiltinFunctionValue).Parent = source
 		}
 
-		vm.stack.Push(member)
+		vm.Stack.Push(member)
 
 	case InstructionBreakpoint:
+		/*
+			// I'm keeping this
+			s := vm.scope
+			log.Printf("breakpoint %d", vm.ip)
+			for s != nil {
+				log.Printf("%s", s.current)
+				s = s.parent
+			}
+		*/
+		vm.Stack.Push(&NilValue{})
 
 	default:
 		panic("invalid byte code")
@@ -832,11 +1028,12 @@ func (vm *VM) Call(v Value, args []Value) (Value, error) {
 		vm.call.Push(Call{
 			chunk: vm.chunk,
 			ip:    vm.ip,
-			stackEnd:    vm.stack.Current,
-			variableEnd: vm.variableEnd,
 			scope: vm.scope,
 		})
 
+		vm.scope = f.Scope
+		vm.descend()
+
 		for i := 0; i < len(f.Params); i++ {
 			vm.addVar(f.Params[i].Name, args[i])
 		}
@@ -845,8 +1042,6 @@ func (vm *VM) Call(v Value, args []Value) (Value, error) {
 			vm.addVar("this", f.Parent)
 		}
 
-		vm.variableEnd = vm.stack.Current
-
 		vm.chunk = f.Chunk
 		vm.ip = 0
 
@@ -855,7 +1050,7 @@ func (vm *VM) Call(v Value, args []Value) (Value, error) {
 
 		vm.Next()
 
-		return vm.stack.Pop(), nil
+		return vm.Stack.Pop(), nil
 
 	case *BuiltinFunctionValue:
 		return f.F(vm, f.Parent, args)
@@ -873,6 +1068,18 @@ func (vm *VM) TryNextByte() (Bytecode, error) {
 		return 0, errors.New("there are no more instructions")
 	}
 
+	for int(vm.ip) >= len(vm.chunk.Bytecode) && vm.call.Current > 0 {
+		c := vm.call.Pop()
+
+		vm.ip = c.ip
+		vm.chunk = c.chunk
+		vm.scope = c.scope
+	}
+
+	if int(vm.ip) >= len(vm.chunk.Bytecode) {
+		return 0, errors.New("there are no more instructions")
+	}
+
 	v := vm.chunk.Bytecode[vm.ip]
 	vm.ip++
 
@@ -890,57 +1097,59 @@ func (vm *VM) NextByte() Bytecode {
 }
 
 func (vm *VM) ascend() {
-	vm.scope--
-
-	if vm.scope < 0 {
+	if vm.scope.parent == nil {
 		panic("invalid scope")
 	}
 
-	vm.purgeVars()
-}
-
-// purgeVars remove all variables not within scope
-func (vm *VM) purgeVars() {
-	for ; vm.variableEnd > 0 && vm.stack.items[vm.variableEnd-1].(*VariableValue).scope > vm.scope; vm.variableEnd-- {
-		vm.stack.Pop()
-	}
+	vm.scope = vm.scope.parent
 }
 
 func (vm *VM) descend() {
-	vm.scope++
+	old := vm.scope
+
+	vm.scope = &Scope{
+		map[string]Value{},
+		old,
+	}
 }
 
 func (vm *VM) addVar(name string, value Value) {
-	vm.variableEnd++
-	vm.stack.Push(&VariableValue{
-		name,
-		value,
-		vm.scope,
-	})
+	vm.scope.current[name] = value
 }
 
-func (vm *VM) getVar(name string) *VariableValue {
-	for i := vm.variableEnd - 1; i >= 0; i-- {
-		v, ok := vm.stack.items[i].(*VariableValue)
+func (vm *VM) getVar(name string) Value {
+	s := vm.scope
 
-		if !ok {
-			continue
-		}
-
-		if v.name == name {
+	for s != nil {
+		if v, ok := s.current[name]; ok {
 			return v
 		}
+
+		s = s.parent
 	}
 
 	return nil
 }
 
+func (vm *VM) setVar(name string, v Value) {
+	s := vm.scope
+
+	for s != nil {
+		if _, ok := s.current[name]; ok {
+			s.current[name] = v
+			break
+		}
+
+		s = s.parent
+	}
+}
+
 func (vm *VM) HasNext() bool {
-	return vm.ip < Pos(len(vm.chunk.Bytecode))
+	return vm.ip < Pos(len(vm.chunk.Bytecode)) || vm.call.Current > 0
 }
 
 func (vm *VM) GetConstant(id Bytecode) Value {
-	return vm.chunk.Constants[id]
+	return vm.chunk.Constants[id].Clone()
 }
 
 func (vm *VM) ReadConstant() Value {

core/vm_test.go

@@ -49,7 +49,7 @@ func TestNewVM(t *testing.T) {
 	chunk := NewChunk([]Bytecode{
 		InstructionConstant, 0,
 	}, []Value{
-		&NumberValue{0},
+		&FloatValue{0},
 	})
 	stackSize := Pos(256)
 	callstackSize := Pos(256)
@@ -76,8 +76,8 @@ func TestNewVM(t *testing.T) {
 	}
 
 	// should have given stack size
-	if vm.stack.Capacity != stackSize {
-		t.Errorf("vm.stack.Capacity = %d, want %d", vm.stack.Capacity, stackSize)
+	if vm.Stack.Capacity != stackSize {
+		t.Errorf("vm.stack.Capacity = %d, want %d", vm.Stack.Capacity, stackSize)
 	}
 
 	// should have given call stack size
@@ -95,23 +95,26 @@ func BenchmarkNewVM(b *testing.B) {
 func GetExecutionTestData() map[string]struct {
 	chunk          *Chunk
 	resultingStack []Value
+	resultingScope []map[string]Value
 } {
 	return map[string]struct {
 		chunk          *Chunk
 		resultingStack []Value
+		resultingScope []map[string]Value
 	}{
 		"two_plus_one": {
 			NewChunk([]Bytecode{
 				InstructionConstant, 0,
 				InstructionConstant, 1,
-				InstructionAdd,
+				InstructionAddFloat,
 			},
 				[]Value{
-					&NumberValue{1}, &NumberValue{2},
+					&FloatValue{1}, &FloatValue{2},
 				}),
 			[]Value{
-				&NumberValue{3},
+				&FloatValue{3},
 			},
+			[]map[string]Value{},
 		},
 		"push_constant": {
 			NewChunk(
@@ -119,12 +122,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionConstant, 0,
 				},
 				[]Value{
-					&NumberValue{1},
+					&FloatValue{1},
 				},
 			),
 			[]Value{
-				&NumberValue{1},
+				&FloatValue{1},
 			},
+			[]map[string]Value{},
 		},
 		"push_true": {
 			NewChunk(
@@ -136,6 +140,7 @@ func GetExecutionTestData() map[string]struct {
 			[]Value{
 				&BoolValue{true},
 			},
+			[]map[string]Value{},
 		},
 		"push_false": {
 			NewChunk(
@@ -147,6 +152,7 @@ func GetExecutionTestData() map[string]struct {
 			[]Value{
 				&BoolValue{false},
 			},
+			[]map[string]Value{},
 		},
 		"push_nil": {
 			NewChunk(
@@ -158,6 +164,7 @@ func GetExecutionTestData() map[string]struct {
 			[]Value{
 				&NilValue{},
 			},
+			[]map[string]Value{},
 		},
 		"empty": {
 			NewChunk(
@@ -165,6 +172,7 @@ func GetExecutionTestData() map[string]struct {
 				[]Value{},
 			),
 			[]Value{},
+			[]map[string]Value{},
 		},
 		// (2 + 1) * 5 / (6 - 2)
 		"full_arithmetic": {
@@ -172,21 +180,22 @@ func GetExecutionTestData() map[string]struct {
 				[]Bytecode{
 					InstructionConstant, 0,
 					InstructionConstant, 1,
-					InstructionAdd,
+					InstructionAddFloat,
 					InstructionConstant, 2,
-					InstructionMul,
+					InstructionMulFloat,
 					InstructionConstant, 3,
 					InstructionConstant, 0,
-					InstructionSub,
-					InstructionDiv,
+					InstructionSubFloat,
+					InstructionDivFloat,
 				},
 				[]Value{
-					&NumberValue{2}, &NumberValue{1}, &NumberValue{5}, &NumberValue{6},
+					&FloatValue{2}, &FloatValue{1}, &FloatValue{5}, &FloatValue{6},
 				},
 			),
 			[]Value{
-				&NumberValue{3.75},
+				&FloatValue{3.75},
 			},
+			[]map[string]Value{},
 		},
 		"equality_true": {
 			NewChunk(
@@ -196,12 +205,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionEquals,
 				},
 				[]Value{
-					&NumberValue{1},
+					&FloatValue{1},
 				},
 			),
 			[]Value{
 				&BoolValue{true},
 			},
+			[]map[string]Value{},
 		},
 		"equality_false": {
 			NewChunk(
@@ -211,12 +221,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionEquals,
 				},
 				[]Value{
-					&NumberValue{1}, &NumberValue{2},
+					&FloatValue{1}, &FloatValue{2},
 				},
 			),
 			[]Value{
 				&BoolValue{false},
 			},
+			[]map[string]Value{},
 		},
 		"inequality_false": {
 			NewChunk(
@@ -226,12 +237,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionNotEqual,
 				},
 				[]Value{
-					&NumberValue{1},
+					&FloatValue{1},
 				},
 			),
 			[]Value{
 				&BoolValue{false},
 			},
+			[]map[string]Value{},
 		},
 		"inequality_true": {
 			NewChunk(
@@ -241,12 +253,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionNotEqual,
 				},
 				[]Value{
-					&NumberValue{1}, &NumberValue{2},
+					&FloatValue{1}, &FloatValue{2},
 				},
 			),
 			[]Value{
 				&BoolValue{true},
 			},
+			[]map[string]Value{},
 		},
 		"not_true": {
 			NewChunk(
@@ -259,6 +272,7 @@ func GetExecutionTestData() map[string]struct {
 			[]Value{
 				&BoolValue{false},
 			},
+			[]map[string]Value{},
 		},
 		"not_false": {
 			NewChunk(
@@ -271,6 +285,7 @@ func GetExecutionTestData() map[string]struct {
 			[]Value{
 				&BoolValue{true},
 			},
+			[]map[string]Value{},
 		},
 		"jump": {
 			NewChunk(
@@ -280,12 +295,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionConstant, 1, // should execute
 				},
 				[]Value{
-					&NumberValue{0}, &NumberValue{1},
+					&FloatValue{0}, &FloatValue{1},
 				},
 			),
 			[]Value{
-				&NumberValue{1},
+				&FloatValue{1},
 			},
+			[]map[string]Value{},
 		},
 		"jump_false/false": {
 			NewChunk(
@@ -296,12 +312,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionConstant, 1, // should execute
 				},
 				[]Value{
-					&NumberValue{0}, &NumberValue{1},
+					&FloatValue{0}, &FloatValue{1},
 				},
 			),
 			[]Value{
-				&NumberValue{1},
+				&FloatValue{1},
 			},
+			[]map[string]Value{},
 		},
 		"jump_false/true": {
 			NewChunk(
@@ -312,12 +329,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionConstant, 1, // should execute
 				},
 				[]Value{
-					&NumberValue{0}, &NumberValue{1},
+					&FloatValue{0}, &FloatValue{1},
 				},
 			),
 			[]Value{
-				&NumberValue{0}, &NumberValue{1},
+				&FloatValue{0}, &FloatValue{1},
 			},
+			[]map[string]Value{},
 		},
 		"declare_local": {
 			NewChunk(
@@ -326,14 +344,13 @@ func GetExecutionTestData() map[string]struct {
 					InstructionDeclareLocal, 1,
 				},
 				[]Value{
-					&NumberValue{0}, &StringValue{"a"},
+					&FloatValue{0}, &StringValue{"a"},
 				},
 			),
-			[]Value{
-				&VariableValue{
-					"a",
-					&NumberValue{0},
-					0,
+			[]Value{&FloatValue{0}},
+			[]map[string]Value{
+				{
+					"a": &FloatValue{0},
 				},
 			},
 		},
@@ -342,18 +359,19 @@ func GetExecutionTestData() map[string]struct {
 				[]Bytecode{
 					InstructionConstant, 0,
 					InstructionDeclareLocal, 1,
+					InstructionPop,
 					InstructionConstant, 2,
 					InstructionSetLocal, 1, // reassign
+					InstructionPop,
 				},
 				[]Value{
-					&NumberValue{0}, &StringValue{"a"}, &NumberValue{1},
+					&FloatValue{0}, &StringValue{"a"}, &FloatValue{1},
 				},
 			),
-			[]Value{
-				&VariableValue{
-					"a",
-					&NumberValue{1},
-					0,
+			[]Value{},
+			[]map[string]Value{
+				{
+					"a": &FloatValue{1},
 				},
 			},
 		},
@@ -362,19 +380,18 @@ func GetExecutionTestData() map[string]struct {
 				[]Bytecode{
 					InstructionConstant, 0,
 					InstructionDeclareLocal, 1,
-					InstructionGetLocal, 1, // reassign
 				},
 				[]Value{
-					&NumberValue{0}, &StringValue{"a"},
+					&FloatValue{0}, &StringValue{"a"},
 				},
 			),
 			[]Value{
-				&VariableValue{
-					"a",
-					&NumberValue{0},
-					0,
+				&FloatValue{0},
+			},
+			[]map[string]Value{
+				{
+					"a": &FloatValue{0},
 				},
-				&NumberValue{0},
 			},
 		},
 		"get_reassigned_local": {
@@ -382,23 +399,25 @@ func GetExecutionTestData() map[string]struct {
 				[]Bytecode{
 					InstructionConstant, 0,
 					InstructionDeclareLocal, 1,
+					InstructionPop,
 					InstructionGetLocal, 1,
 					InstructionConstant, 2,
 					InstructionSetLocal, 1, // reassign
+					InstructionPop,
 					InstructionGetLocal, 1,
 				},
 				[]Value{
-					&NumberValue{0}, &StringValue{"a"}, &NumberValue{1},
+					&FloatValue{0}, &StringValue{"a"}, &FloatValue{1},
 				},
 			),
 			[]Value{
-				&VariableValue{
-					"a",
-					&NumberValue{1},
-					0,
+				&FloatValue{0},
+				&FloatValue{1},
+			},
+			[]map[string]Value{
+				{
+					"a": &FloatValue{1},
 				},
-				&NumberValue{0},
-				&NumberValue{1},
 			},
 		},
 		"variable_scope": {
@@ -406,26 +425,28 @@ func GetExecutionTestData() map[string]struct {
 				[]Bytecode{
 					InstructionConstant, 0,
 					InstructionDeclareLocal, 1,
+					InstructionPop,
 					InstructionDescend,
 					InstructionConstant, 2,
 					InstructionDeclareLocal, 3,
+					InstructionPop,
 					InstructionDescend,
 					InstructionConstant, 4,
 					InstructionDeclareLocal, 5,
+					InstructionPop,
 					InstructionAscend,
 					InstructionAscend,
 				},
 				[]Value{
-					&NumberValue{0}, &StringValue{"a"},
-					&NumberValue{1}, &StringValue{"b"},
-					&NumberValue{2}, &StringValue{"c"},
+					&FloatValue{0}, &StringValue{"a"},
+					&FloatValue{1}, &StringValue{"b"},
+					&FloatValue{2}, &StringValue{"c"},
 				},
 			),
-			[]Value{
-				&VariableValue{
-					"a",
-					&NumberValue{0},
-					0,
+			[]Value{},
+			[]map[string]Value{
+				{
+					"a": &FloatValue{0},
 				},
 			},
 		},
@@ -438,25 +459,25 @@ func GetExecutionTestData() map[string]struct {
 					InstructionCall,
 				},
 				[]Value{
-					&NumberValue{1},
-					&NumberValue{2},
+					&FloatValue{1},
+					&FloatValue{2},
 					&FunctionValue{
 						Name: "sum",
 						Params: []FunctionParameter{
 							{
 								"a",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 							{
 								"b",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 						},
 						Chunk: NewChunk(
 							[]Bytecode{
 								InstructionGetLocal, 0,
 								InstructionGetLocal, 1,
-								InstructionAdd,
+								InstructionAddFloat,
 								InstructionReturn,
 							},
 							[]Value{
@@ -467,32 +488,34 @@ func GetExecutionTestData() map[string]struct {
 				},
 			),
 			[]Value{
-				&NumberValue{3},
+				&FloatValue{3},
 			},
+			[]map[string]Value{},
 		},
 		"function_calling_function": {
 			NewChunk(
 				[]Bytecode{
 					InstructionConstant, 3,
 					InstructionDeclareLocal, 4,
+					InstructionPop,
 					InstructionConstant, 0,
 					InstructionConstant, 1,
 					InstructionConstant, 2,
 					InstructionCall,
 				},
 				[]Value{
-					&NumberValue{1},
-					&NumberValue{2},
+					&FloatValue{1},
+					&FloatValue{2},
 					&FunctionValue{
 						Name: "sum",
 						Params: []FunctionParameter{
 							{
 								"a",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 							{
 								"b",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 						},
 						Chunk: NewChunk(
@@ -501,7 +524,7 @@ func GetExecutionTestData() map[string]struct {
 								InstructionGetLocal, 2, InstructionCall, // square the number
 								InstructionGetLocal, 1,
 								InstructionGetLocal, 2, InstructionCall, // square the number
-								InstructionAdd,
+								InstructionAddFloat,
 								InstructionReturn,
 							},
 							[]Value{
@@ -514,14 +537,14 @@ func GetExecutionTestData() map[string]struct {
 						Params: []FunctionParameter{
 							{
 								"n",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 						},
 						Chunk: NewChunk(
 							[]Bytecode{
 								InstructionGetLocal, 0,
 								InstructionGetLocal, 0,
-								InstructionMul,
+								InstructionMulFloat,
 								InstructionReturn,
 							},
 							[]Value{
@@ -533,21 +556,23 @@ func GetExecutionTestData() map[string]struct {
 				},
 			),
 			[]Value{
-				&VariableValue{
-					"square",
-					&FunctionValue{
+				&FloatValue{5},
+			},
+			[]map[string]Value{
+				{
+					"square": &FunctionValue{
 						Name: "square",
 						Params: []FunctionParameter{
 							{
 								"n",
-								&NumberSignature{},
+								&FloatSignature{},
 							},
 						},
 						Chunk: NewChunk(
 							[]Bytecode{
 								InstructionGetLocal, 0,
 								InstructionGetLocal, 0,
-								InstructionMul,
+								InstructionMulFloat,
 								InstructionReturn,
 							},
 							[]Value{
@@ -555,9 +580,7 @@ func GetExecutionTestData() map[string]struct {
 							},
 						),
 					},
-					0,
 				},
-				&NumberValue{5},
 			},
 		},
 		"list_concat": {
@@ -570,13 +593,13 @@ func GetExecutionTestData() map[string]struct {
 				[]Value{
 					&ListValue{
 						[]Value{
-							&NumberValue{1},
-							&NumberValue{2},
+							&FloatValue{1},
+							&FloatValue{2},
 						},
 					},
 					&ListValue{
 						[]Value{
-							&NumberValue{3},
+							&FloatValue{3},
 						},
 					},
 				},
@@ -584,12 +607,13 @@ func GetExecutionTestData() map[string]struct {
 			[]Value{
 				&ListValue{
 					[]Value{
-						&NumberValue{1},
-						&NumberValue{2},
-						&NumberValue{3},
+						&FloatValue{1},
+						&FloatValue{2},
+						&FloatValue{3},
 					},
 				},
 			},
+			[]map[string]Value{},
 		},
 	}
 }
@@ -604,7 +628,7 @@ func TestVM_Execution(t *testing.T) {
 			for vm.Next() {
 			}
 
-			CompareStacks(t, test.resultingStack, vm.stack)
+			CompareStacks(t, test.resultingStack, vm.Stack)
 		})
 	}
 }
@@ -630,7 +654,7 @@ func TestVM_NextByte(t *testing.T) {
 				InstructionConstant, 0,
 			},
 			[]Value{
-				&NumberValue{0},
+				&FloatValue{0},
 			},
 		),
 		16,
@@ -741,7 +765,7 @@ func TestVM_Jump(t *testing.T) {
 				InstructionConstant, 2,
 			},
 			[]Value{
-				&NumberValue{0}, &NumberValue{1}, &NumberValue{2},
+				&FloatValue{0}, &FloatValue{1}, &FloatValue{2},
 			},
 		),
 		16,
@@ -766,7 +790,7 @@ func TestVM_JumpFalse(t *testing.T) {
 				InstructionConstant, 2,
 			},
 			[]Value{
-				&NumberValue{0}, &NumberValue{1}, &NumberValue{2},
+				&FloatValue{0}, &FloatValue{1}, &FloatValue{2},
 			},
 		),
 		16,
@@ -792,7 +816,7 @@ func TestVM_DontJumpFalse(t *testing.T) {
 				InstructionConstant, 2,
 			},
 			[]Value{
-				&NumberValue{0}, &NumberValue{1}, &NumberValue{2},
+				&FloatValue{0}, &FloatValue{1}, &FloatValue{2},
 			},
 		),
 		16,

era3.ang

@@ -0,0 +1,11 @@
+fn counter() -> (fn() -> int) {
+    i := 0
+
+    fn() -> int { i = i + 1 }
+}
+
+next := counter()
+
+println(next())
+println(next())
+println(next())

examples/pi-approx.ang

@@ -7,19 +7,19 @@
 terms := 1000000
 
 # The running sum of terms
-tot := 0
+tot := 0.0
 
 n := 1
 while n <= terms {
-	tot = tot + 1 / (n*n)
+	tot = tot + 1.0/float(n*n)
 	n = n + 1
 }
 
-tot = tot * 6
+tot = tot * 6.0
 
 # get the absolute value of a number
-func abs(x: number) number {
-	if x < 0 {
+fn abs(x: float) -> float {
+	if x < 0.0 {
 		return -x
 	}
 	return x
@@ -30,19 +30,19 @@ func abs(x: number) number {
 # see: https://en.wikipedia.org/wiki/Newton's_method
 # The required accuracy
 SQRT_ACC := 0.00000001
-func sqrt(x: number) number {
-    pg := 0 # previous guess
-    g := 1 # current guess
+fn sqrt(x: float) -> float {
+    pg := 0.0 # previous guess
+    g := 1.0 # current guess
 
     while abs(pg - g) >= SQRT_ACC {
         pg = g
-        g = (pg + tot/pg)/2
+        g = (pg + x/pg)/2.0
     }
 
     return g
 }
 
-tot = sqrt(tot)
+pi := sqrt(tot)
 
 # output the result
-write(str(tot))
+println(pi)

lib/honning.ang

@@ -13,3 +13,5 @@ _slow_blink := CSI + "5m"
 _rapid_blink := CSI + "6m"
 _strike := CSI + "9m"
 _primary_font := CSI + "10m"
+
+fn red(s: string) -> string {}

lib/list.ang

@@ -1,5 +1,5 @@
 
-func map(list: list[any], f: func(any)any) list[any] {
+fn map(list: [any], f: fn(any) -> any) -> [any] {
     out := []
 
     i := 0

lib/math.ang

@@ -7,7 +7,7 @@ E := 2.718281828459045235360287471352
 #   Get the absolute value of a number. If x is negative, the returned
 #   value is positive and equal to `-x`. If x is positive or zero, the
 #   returned value is x.
-func abs(x: number) number {
+fn absf(x: float) -> float {
     # if the number is negative
     if x < 0 {
         # negate it so it's positive
@@ -17,15 +17,23 @@ func abs(x: number) number {
     return x
 }
 
+fn absi(n: int) -> int {
+    if n < 0 {
+        -n
+    } else {
+        n
+    }
+}
+
 DERIVE_DX := 0.00000001
-func derive(f: func(number)number, x: number) number {
+fn derive(f: fn(float) -> float, x: float) float {
     return (f(x + DERIVE_DX) - f(x))/DERIVE_DX
 }
 
 NEWTONS_ACC := 0.000000000001
-func newtons(f: func(number)number) number {
-    pg := 0
-    g := 1
+fn newtons(f: fn(float) -> float) -> float {
+    pg := 0.0
+    g := 1.0
 
     while abs(g - pg) > NEWTONS_ACC {
         pg = g
@@ -41,9 +49,9 @@ MAX_SQRT_DX := 0.0000001
 # x: number
 #   Calculate the approximate square root using newton's method until
 #   the accuracy has increased by less than the variable `MAX_SQRT_DX`.
-func sqrt(x: number) number {
+fn sqrt(x: float) -> float {
     ng := x
-    g := 1
+    g := 1.0
 
     while abs(g - ng) > MAX_SQRT_DX {
         g = ng
@@ -51,8 +59,6 @@ func sqrt(x: number) number {
         # create new guess
         ng = (g + x / g) / 2
     }
-
-    return g
 }
 
 # floor(x)
@@ -72,7 +78,7 @@ func sqrt(x: number) number {
 # round(x)
 # x: number
 #   Return the closest whole number to the value x.
-func round(x: number) number {
+fn round(x: float) -> float {
     f := floor(x)
 
     if x - f > 0.5 {
@@ -86,7 +92,7 @@ func round(x: number) number {
 # x: number; any number
 # n: number; the number to divide by
 #   Return the rest from a division of x by n.
-func mod(x: number, n: number) number {
+fn mod(x: float, n: float) -> float {
     if x == 0 {
         return 0
     }
@@ -110,17 +116,18 @@ func mod(x: number, n: number) number {
 #   This value is only reasonable if 0<x<1.
 #   It is approximated using the taylor series of e**x.
 SM_EXP_ACC := 0.00000000001
-func sm_exp(x: number) number {
-    p_tot := 0
-    tot := 1
+fn sm_exp(x: float) -> float {
+    p_tot := 0.0
+    tot := 1.0
     n := 1
     x_pow := x
-    f := 1
+    f := 1.0
+
     while abs(tot - p_tot) > SM_EXP_ACC {
         p_tot = tot
         t := x_pow / f
         tot = tot + t
-        f = f * (n+1)
+        f = f * float(n+1)
         x_pow = x_pow * x
         n = n + 1
     }
@@ -131,22 +138,22 @@ func sm_exp(x: number) number {
 # exp(x)
 # x: number; any number
 #   Get an approximate value of e raised to the power of x.
-func exp(x: number) number {
+fn exp(x: float) -> float {
     n := abs(x)
-    tot := 1
+    tot := 1.0
     while n >= 1 {
         tot = tot * E
         n = n - 1
     }
 
-    if n > 0 {
+    if n > 0.0 {
         tot = tot * sm_exp(n)
     }
 
     if x < 0 {
-        return 1/tot
+        1.0/tot
     } else {
-        return tot
+        tot
     }
 }
 
@@ -155,9 +162,9 @@ func exp(x: number) number {
 #   Get the approximate value of the natural logarithm
 #   This function uses newton's method to approximate.
 LN_ACC := 0.0000000001
-func ln(x: number) number {
-    pg := 0
-    g := 1
+fn ln(x: float) -> float {
+    pg := 0.0
+    g := 1.0
 
     while abs(pg - g) > LN_ACC {
         pg = g
@@ -171,7 +178,7 @@ func ln(x: number) number {
 # x: number; any number. The base
 # p: number; the value of the exponent
 #   Raise any number to any power (x^p)
-func pow(x: number, p: number) number {
+fn pow(x: float, p: float) -> float {
     return exp(p*ln(x))
 }
 
@@ -181,15 +188,15 @@ func pow(x: number, p: number) number {
 #   Calculate the approximate value of the logarithm
 #   of a with b as base.
 LOG_ACC := 0.0000001
-func log(a: number, b: number) number {
+fn log(a: float, b: float) -> float {
     ln_b := ln(b)
 
-    pg := 0
-    g := 1
+    pg := 0.0
+    g := 1.0
 
     while abs(g - pg) > LOG_ACC {
         pg = g
-        g = pg - 1/ln_b - a/(ln_b*pow(b, pg))
+        g = pg - 1.0/ln_b - a/(ln_b*pow(b, pg))
     }
 
     return g
@@ -199,9 +206,9 @@ func log(a: number, b: number) number {
 # x: number; an angle in radians
 #   Get the sine of an angle (in radians). https://en.wikipedia.org/wiki/Sine_and_cosine
 #   TODO: use hashmap with precomputed values and linear interpolation
-func sin(x: number) number {
-    f := 1
-    x = mod(x, 2*PI)
+fn sin(x: float) -> float {
+    f := 1.0
+    x = mod(x, 2.0*PI)
     if x > PI {
         x = PI - x
         f = -1
@@ -209,13 +216,13 @@ func sin(x: number) number {
 
     # compute sine with a taylor series mock function of sine (valid between -pi and +pi)
     tot := x
-    l := 1
-    i := 1
-    s := -1
+    l := 1.0
+    i := 1.0
+    s := -1.0
 
     while i <= 19 {
-        i = i + 2
-        l = s * l * x / i / (i-1)
+        i = i + 2.0
+        l = s * l * x / i / (i-1.0)
 
         tot = tot + l
 

tests/arithmetics.ang

@@ -1,5 +1,5 @@
 assertEq(1+1, 2)
 assertEq(3*2, 6)
-assertEq(3/4, 0.75)
+assertEq(3.0/4.0, 0.75)
 assertEq(2 - 5, -3)
 

tests/conditions.ang

@@ -3,7 +3,7 @@ assertEq(1, 1)
 assertEq(0, 0)
 assertEq("", "")
 
-assertEq([]number, []number)
+assertEq([]int, []int)
 assertEq([3, 1, 4, 1], [3, 1, 4, 1])
 
 # Inequality

tests/list.ang

@@ -1,20 +1,20 @@
-list := []number
+list := []int
 
 x := 1
 while x <= 1000 {
     list.append(x)
-    assertEq(list.reduce(func(tot: number, a: number) number {
+    assertEq(list.reduce(fn(tot: int, a: int) -> int {
         return tot + a
     }, 0), x*(x + 1)/2)
 
     x = x + 1
 }
 
-func sum(a: number, b: number) number {
+fn sum(a: int, b: int) -> int {
     return a + b
 }
 
-list = []number
+list = []int
 x = 1
 while x <= 100 {
     list.append(2*x - 1)

tests/recursive_fib.ang

@@ -3,7 +3,7 @@ fibonacci_numbers := [
     0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377
 ]
 
-func fib(n: number) number {
+fn fib(n: int) -> int {
     if n < 2 {
         return n
     }
@@ -29,4 +29,4 @@ while x < fibonacci_numbers.length() {
     x = x + 1
 }
 
-write("")
+println("")

tests/refs.ang

@@ -1,5 +1,5 @@
 
-list := []number
+list := []int
 
 list.append(1)
 list.append(2)

tests/simple_func.ang

@@ -1,12 +1,8 @@
 
-func sum(a: number, b: number) number {
+fn sum(a: int, b: int) -> int {
     return a + b
 }
 
-breakpoint
 
 assertEq(sum(1, 2), 3)
-breakpoint
-
 assertEq(sum(3, 3), 6)
-breakpoint

tests/types.ang

@@ -1,8 +1,8 @@
 
-assertEq(type(1), "number")
+assertEq(type(1), "int")
 assertEq(type("Hello"), "string")
 assertEq(type(true), "boolean")
 
 # lists
 assertEq(type(["Hello", "world"]), "list[string]")
-assertEq(type([0, 1]), "list[number]")
+assertEq(type([0, 1]), "list[int]")