Add importing, lists and objects, and add basic functions (global and on values)

cli/main.go

@@ -5,6 +5,7 @@ import (
 	"log"
 	"neemek.com/anglais/core"
 	"os"
+	"path/filepath"
 )
 
 type Context struct {
@@ -16,6 +17,37 @@ type RunCmd struct {
 	File     string `arg:"" name:"file" help:"File to read program from" type:"existingfile"`
 }
 
+// WorkingDirectoryResolver resolves imports relative to the working directory
+type WorkingDirectoryResolver struct {
+	workingDirectory string
+}
+
+func (r *WorkingDirectoryResolver) Resolve(path string) (core.Node, error) {
+	pth := filepath.Join(r.workingDirectory, path)
+	f, err := os.ReadFile(pth)
+	if err != nil {
+		return nil, err
+	}
+
+	str := string(f)
+
+	l := core.NewLexer(str)
+
+	tokens, err := l.Tokenize()
+	if err != nil {
+		return nil, err
+	}
+
+	p := core.NewParser(tokens)
+
+	tree, err := p.Parse()
+	if err != nil {
+		return nil, err
+	}
+
+	return tree, nil
+}
+
 func (cmd *RunCmd) Run(ctx *Context) error {
 	if ctx.Debug {
 		log.Println("Reading file")
@@ -72,6 +104,15 @@ func (cmd *RunCmd) Run(ctx *Context) error {
 		}
 		c := core.NewCompiler()
 
+		if ctx.Debug {
+			log.Println("Setting imports resolver")
+		}
+
+		dir, _ := filepath.Split(cmd.File)
+		c.SetImportsResolver(&WorkingDirectoryResolver{
+			dir,
+		})
+
 		if ctx.Debug {
 			log.Println("Compiling parse tree")
 		}
@@ -162,8 +203,18 @@ func (cmd *CompileCmd) Run(ctx *Context) error {
 	if ctx.Debug {
 		log.Println("Initialized compiler")
 	}
+
 	c := core.NewCompiler()
 
+	if ctx.Debug {
+		log.Println("Setting import resolver")
+	}
+
+	dir, _ := filepath.Split(cmd.File)
+	c.SetImportsResolver(&WorkingDirectoryResolver{
+		dir,
+	})
+
 	if ctx.Debug {
 		log.Println("Compiling parse tree")
 	}

core/compiler.go

@@ -5,9 +5,16 @@ type Compiler struct {
 	ip    Pos
 	scope Pos
 
+	imports  map[string]Node
+	resolver ImportsResolver
+
 	stack *Stack[LocalVariable]
 }
 
+type ImportsResolver interface {
+	Resolve(path string) (Node, error)
+}
+
 type LocalVariable struct {
 	name  string
 	scope int
@@ -19,6 +26,7 @@ func NewCompiler() *Compiler {
 		ip:      0,
 		scope:   0,
 		stack:   NewStack[LocalVariable](256),
+		imports: make(map[string]Node),
 	}
 
 	return c
@@ -63,6 +71,14 @@ func (c *Compiler) Compile(tree Node) {
 		c.add(InstructionConstant)
 		c.addConstant(tree.(*NumberNode).value)
 
+	case ListNodeType:
+		v := tree.(*ListNode).items
+		c.add(InstructionNewList)
+		for _, n := range v {
+			c.Compile(n)
+			c.add(InstructionAppend)
+		}
+
 	case ReferenceNodeType:
 		c.getVar(tree.(*ReferenceNode).name)
 
@@ -155,7 +171,7 @@ func (c *Compiler) Compile(tree Node) {
 			c.Compile(arg)
 		}
 
-		c.getVar(n.name)
+		c.Compile(n.source)
 
 		c.add(InstructionCall)
 
@@ -194,12 +210,28 @@ func (c *Compiler) Compile(tree Node) {
 			n.name,
 			n.params,
 			c.Chunk,
+			nil,
 		}
 
 		// restore old chunk and ip
 		c.Chunk = mc
 		c.ip = mip
 
+	case AccessNodeType:
+		n := tree.(*AccessNode)
+		c.Compile(n.source)
+		c.add(InstructionAccessProperty)
+		c.addConstant(StringValue(n.property))
+
+	case ImportNodeType:
+		n := tree.(*ImportNode)
+
+		t := c.resolveImport(n.path).(*BlockNode)
+
+		for _, statement := range t.statements {
+			c.Compile(statement)
+		}
+
 	case ReturnNodeType:
 		c.Compile(tree.(*ReturnNode).value)
 		c.add(InstructionReturn)
@@ -305,6 +337,26 @@ func (c *Compiler) descend() {
 	}
 }
 
+func (c *Compiler) resolveImport(path string) Node {
+	if chunk, ok := c.imports[path]; ok {
+		return chunk
+	}
+
+	// find tree
+	tree, err := c.resolver.Resolve(path)
+	if err != nil {
+		panic(err)
+	}
+
+	c.imports[path] = tree
+
+	return tree
+}
+
+func (c *Compiler) SetImportsResolver(resolver ImportsResolver) {
+	c.resolver = resolver
+}
+
 func (c *Compiler) advance(amount Pos) {
 	c.ip += amount
 }

core/compiler_test.go

@@ -267,6 +267,7 @@ func GetCompileTestData() map[string]CompileTestData {
 								StringValue("a"), StringValue("b"),
 							},
 						),
+						nil,
 					},
 					0,
 				},
@@ -296,7 +297,9 @@ func GetCompileTestData() map[string]CompileTestData {
 						true,
 					},
 					&CallNode{
+						&ReferenceNode{
 							"a",
+						},
 						[]Node{},
 						false,
 					},
@@ -321,6 +324,7 @@ func GetCompileTestData() map[string]CompileTestData {
 								NumberValue(1), StringValue("b"),
 							},
 						),
+						nil,
 					},
 					0,
 				},

core/lexer.go

@@ -34,6 +34,8 @@ const (
 
 	TokenOpenParenthesis
 	TokenCloseParenthesis
+	TokenOpenBracket
+	TokenCloseBracket
 	TokenOpenBrace
 	TokenCloseBrace
 
@@ -47,6 +49,7 @@ const (
 	TokenVar
 	TokenIf
 	TokenElse
+	TokenImport
 
 	TokenComma
 	TokenDot
@@ -144,6 +147,10 @@ func (t TokenType) String() string {
 		return "double ampersand"
 	case TokenDoublePipe:
 		return "double pipe"
+	case TokenOpenBracket:
+		return "open bracket"
+	case TokenCloseBracket:
+		return "close bracket"
 	}
 
 	return "UNDEFINED TOKENTYPE STRING CONVERSION"
@@ -210,6 +217,10 @@ func (l *Lexer) NextToken() (Token, error) {
 		return l.makeToken(TokenOpenParenthesis), nil
 	case ')':
 		return l.makeToken(TokenCloseParenthesis), nil
+	case '[':
+		return l.makeToken(TokenOpenBracket), nil
+	case ']':
+		return l.makeToken(TokenCloseBracket), nil
 	case '{':
 		return l.makeToken(TokenOpenBrace), nil
 	case '}':
@@ -309,6 +320,8 @@ func (l *Lexer) NextToken() (Token, error) {
 				return l.makeToken(TokenBreakpoint), nil
 			case "return":
 				return l.makeToken(TokenReturn), nil
+			case "import":
+				return l.makeToken(TokenImport), nil
 			default:
 				return l.makeToken(TokenName), nil
 			}

core/lexer_test.go

@@ -122,6 +122,12 @@ func GetLexerTestData() map[string]LexerTestData {
 				TokenOpenBrace, TokenReturn, TokenName, TokenPlus, TokenName, TokenCloseBrace,
 			},
 		},
+		"list": {
+			"data := [3, 1, 4, 1]",
+			[]TokenType{
+				TokenName, TokenDeclare, TokenOpenBracket, TokenNumber, TokenComma, TokenNumber, TokenComma, TokenNumber, TokenComma, TokenNumber, TokenCloseBracket,
+			},
+		},
 	}
 }
 

core/nodes.go

@@ -19,6 +19,7 @@ const (
 	ReferenceNodeType
 	BooleanNodeType
 	NilNodeType
+	ListNodeType
 	BinaryNodeType
 	BlockNodeType
 	ConditionalNodeType
@@ -27,6 +28,8 @@ const (
 	CallNodeType
 	FunctionNodeType
 	ReturnNodeType
+	AccessNodeType
+	ImportNodeType
 	BreakpointNodeType
 )
 
@@ -58,6 +61,14 @@ func (n NodeType) String() string {
 		return "Function"
 	case ReturnNodeType:
 		return "Return"
+	case ListNodeType:
+		return "List"
+	case AccessNodeType:
+		return "Access"
+	case BreakpointNodeType:
+		return "Breakpoint"
+	case ImportNodeType:
+		return "Import"
 	}
 	return "Invalid Node Type"
 }
@@ -101,6 +112,41 @@ func (n NumberNode) String() string {
 	return strconv.FormatFloat(float64(n.value), 'g', -1, NumberSize)
 }
 
+// ListNode a list or sequence of values (items)
+type ListNode struct {
+	items []Node
+}
+
+func (n ListNode) Type() NodeType {
+	return ListNodeType
+}
+
+func (n ListNode) String() string {
+	sb := strings.Builder{}
+	sb.WriteString("[")
+	for i, item := range n.items {
+		sb.WriteString(item.String())
+		if i > 0 {
+			sb.WriteString(", ")
+		}
+	}
+	sb.WriteString("]")
+	return sb.String()
+}
+
+type AccessNode struct {
+	source   Node
+	property string
+}
+
+func (n AccessNode) Type() NodeType {
+	return AccessNodeType
+}
+
+func (n AccessNode) String() string {
+	return fmt.Sprintf("(%s from %s)", n.property, n.source)
+}
+
 type BinaryOperation uint
 
 func (n BinaryOperation) String() string {
@@ -125,6 +171,10 @@ func (n BinaryOperation) String() string {
 		return "less or equal"
 	case BinaryGreaterEqual:
 		return "greater or equal"
+	case BinaryAnd:
+		return "and"
+	case BinaryOr:
+		return "or"
 	}
 
 	return "undefined arithmetic operation"
@@ -207,6 +257,18 @@ func (n BlockNode) String() string {
 	return builder.String()
 }
 
+type ImportNode struct {
+	path string
+}
+
+func (n ImportNode) Type() NodeType {
+	return ImportNodeType
+}
+
+func (n ImportNode) String() string {
+	return fmt.Sprintf("import %s", n.path)
+}
+
 // ConditionalNode conditionals (if statements)
 type ConditionalNode struct {
 	condition Node
@@ -253,7 +315,7 @@ func (n AssignNode) String() string {
 
 // function call
 type CallNode struct {
-	name string
+	source Node
 	args   []Node
 	keep   bool
 }
@@ -263,7 +325,7 @@ func (n CallNode) Type() NodeType {
 }
 
 func (n CallNode) String() string {
-	return fmt.Sprintf("call %s with args (%s)", n.name, n.args)
+	return fmt.Sprintf("call %s with args (%s)", n.source.String(), n.args)
 }
 
 // definition of function

core/parser.go

@@ -176,6 +176,30 @@ func (p *Parser) factor() (Node, error) {
 		p.advance()
 		return &NilNode{}, nil
 
+	case TokenOpenBracket:
+		p.advance()
+
+		var values []Node
+		for !p.accept(TokenCloseBracket) {
+			if len(values) > 0 {
+				if err := p.expect(TokenComma); err != nil {
+					return nil, err
+				}
+			}
+
+			value, err := p.condition()
+
+			if err != nil {
+				return nil, err
+			}
+
+			values = append(values, value)
+		}
+
+		return &ListNode{
+			values,
+		}, nil
+
 	// unary minus
 	case TokenMinus:
 		p.advance()
@@ -200,7 +224,9 @@ func (p *Parser) factor() (Node, error) {
 			}
 
 			return &CallNode{
+				&ReferenceNode{
 					name,
+				},
 				args,
 				true,
 			}, nil
@@ -247,8 +273,44 @@ func (p *Parser) factor() (Node, error) {
 	}
 }
 
+func (p *Parser) prop() (Node, error) {
+	v, err := p.factor()
+	if err != nil {
+		return nil, err
+	}
+
+	// parse chains of prop-getting ( "".split().join().length.round() )
+	for p.accept(TokenDot) {
+		if err := p.expect(TokenName); err != nil {
+			return nil, err
+		}
+		property := (*p.prev).Lexeme
+
+		v = &AccessNode{
+			v,
+			property,
+		}
+
+		// if called, also add
+		if (*p.curr).Type == TokenOpenParenthesis {
+			args, err := p.parseArgs()
+			if err != nil {
+				return nil, err
+			}
+
+			v = &CallNode{
+				v,
+				args,
+				true,
+			}
+		}
+	}
+
+	return v, nil
+}
+
 func (p *Parser) product() (Node, error) {
-	left, err := p.factor()
+	left, err := p.prop()
 	if err != nil {
 		return nil, err
 	}
@@ -260,7 +322,7 @@ func (p *Parser) product() (Node, error) {
 			op = BinaryDivision
 		}
 
-		f, err := p.factor()
+		f, err := p.prop()
 		if err != nil {
 			return nil, err
 		}
@@ -414,14 +476,49 @@ func (p *Parser) statement() (Node, error) {
 		p.advance()
 		name := (*p.prev).Lexeme
 
-		if p.curr.Type == TokenOpenParenthesis {
+		if (*p.curr).Type == TokenDot {
+			var v Node = &ReferenceNode{
+				name,
+			}
+
+			// parse chains of prop-getting ( "".split().join().length.round() )
+			for p.accept(TokenDot) {
+				if err := p.expect(TokenName); err != nil {
+					return nil, err
+				}
+				property := (*p.prev).Lexeme
+
+				v = &AccessNode{
+					v,
+					property,
+				}
+
+				// if called, also add
+				if (*p.curr).Type == TokenOpenParenthesis {
+					args, err := p.parseArgs()
+					if err != nil {
+						return nil, err
+					}
+
+					v = &CallNode{
+						v,
+						args,
+						(*p.curr).Type == TokenDot, // if the chain is continued, keep the value.
+					}
+				}
+			}
+
+			return v, nil
+		} else if p.curr.Type == TokenOpenParenthesis {
 			args, err := p.parseArgs()
 			if err != nil {
 				return nil, err
 			}
 
 			return &CallNode{
+				&ReferenceNode{
 					name,
+				},
 				args,
 				false,
 			}, nil
@@ -441,6 +538,19 @@ func (p *Parser) statement() (Node, error) {
 			return p.condition()
 		}
 
+	case TokenImport:
+		p.advance()
+
+		if err := p.expect(TokenString); err != nil {
+			return nil, err
+		}
+
+		path := p.prev.Lexeme[1 : len(p.prev.Lexeme)-1]
+
+		return &ImportNode{
+			path,
+		}, nil
+
 	case TokenFunc:
 		p.advance()
 

core/parser_test.go

@@ -426,6 +426,91 @@ func GetTokenTestData() map[string]TokenTestData {
 				},
 			},
 		},
+		"prop_getting": {
+			[]Token{
+				NewToken(TokenName, 0, 1, 0, "p"),
+				NewToken(TokenDeclare, 1, 2, 0, ":="),
+				NewToken(TokenName, 3, 1, 0, "a"),
+				NewToken(TokenDot, 4, 1, 0, "."),
+				NewToken(TokenName, 5, 1, 0, "b"),
+
+				NewToken(TokenEOF, 23, 0, 2, ""),
+			},
+			&BlockNode{
+				[]Node{
+					&AssignNode{
+						"p",
+						&AccessNode{
+							&ReferenceNode{
+								"a",
+							},
+							"b",
+						},
+						true,
+					},
+				},
+			},
+		},
+		"list_init": {
+			[]Token{
+				NewToken(TokenName, 0, 4, 0, "data"),
+				NewToken(TokenDeclare, 4, 2, 0, ":="),
+
+				NewToken(TokenOpenBracket, 6, 1, 0, "["),
+				NewToken(TokenName, 8, 1, 0, "a"),
+				NewToken(TokenComma, 11, 1, 0, ","),
+
+				NewToken(TokenNumber, 8, 1, 0, "3.141"),
+				NewToken(TokenComma, 11, 1, 0, ","),
+
+				NewToken(TokenString, 6, 1, 0, "\"Hello world!\""),
+				NewToken(TokenComma, 11, 1, 0, ","),
+
+				NewToken(TokenTrue, 6, 1, 0, "true"),
+				NewToken(TokenComma, 11, 1, 0, ","),
+
+				NewToken(TokenOpenBracket, 6, 1, 0, "["),
+				NewToken(TokenNumber, 6, 1, 0, "2"),
+				NewToken(TokenComma, 11, 1, 0, ","),
+
+				NewToken(TokenNumber, 6, 1, 0, "3"),
+				NewToken(TokenCloseBracket, 6, 1, 0, "]"),
+
+				NewToken(TokenCloseBracket, 6, 1, 0, "]"),
+
+				NewToken(TokenEOF, 23, 0, 2, ""),
+			},
+			&BlockNode{
+				[]Node{
+					&AssignNode{
+						"data",
+						&ListNode{
+							[]Node{
+								&ReferenceNode{
+									"a",
+								},
+								&NumberNode{
+									3.141,
+								},
+								&StringNode{
+									"Hello world!",
+									"\"Hello world!\"",
+								},
+								&BooleanNode{
+									true,
+								},
+								&ListNode{
+									[]Node{
+										&NumberNode{2}, &NumberNode{3},
+									},
+								},
+							},
+						},
+						true,
+					},
+				},
+			},
+		},
 	}
 }
 
@@ -533,11 +618,7 @@ func NodeEquality(t *testing.T, n1 Node, n2 Node) {
 		n := n1.(*CallNode)
 		m := n2.(*CallNode)
 
-		if n.name != m.name {
-			t.Errorf("Call node names don't match (%s and %s)", n.name, m.name)
-		} else {
-			t.Logf("Call node names match (%s)", n.name)
-		}
+		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)

core/values.go

@@ -1,8 +1,12 @@
 package core
 
 import (
+	"errors"
 	"fmt"
+	"reflect"
+	"slices"
 	"strconv"
+	"strings"
 )
 
 type ValueType int
@@ -12,6 +16,8 @@ const (
 	BoolValueType
 	NumberValueType
 	StringValueType
+	ListValueType
+	ObjectValueType
 	FunctionValueType
 	BuiltinFunctionValueType
 	VariableValueType
@@ -23,10 +29,14 @@ func (v ValueType) String() string {
 		return "nil"
 	case BoolValueType:
 		return "bool"
+	case ObjectValueType:
+		return "object"
 	case NumberValueType:
 		return "number"
 	case StringValueType:
 		return "string"
+	case ListValueType:
+		return "list"
 	case FunctionValueType:
 		return "function"
 	case BuiltinFunctionValueType:
@@ -38,30 +48,55 @@ func (v ValueType) String() string {
 	return "undefined"
 }
 
-func GetType(v string) ValueType {
-	switch v {
-	case "nil":
-		return NilValueType
-	case "bool":
-		return BoolValueType
-	case "number":
-		return NumberValueType
-	case "string":
-		return StringValueType
-	case "function":
-		return FunctionValueType
-	case "builtin":
-		return BuiltinFunctionValueType
-	case "variable":
-		return VariableValueType
+// GoToValue convert go values to anglais VM-values. Works for some values (nil, bool, float64, string, slices, maps)
+func GoToValue(gov interface{}) Value {
+	switch v := gov.(type) {
+	case nil:
+		return NilValue{}
+	case bool:
+		return BoolValue(v)
+	case float64:
+		return NumberValue(v)
+	case string:
+		return StringValue(v)
+	case []interface{}:
+		values := make([]Value, len(v))
+		for i, value := range v {
+			values[i] = GoToValue(value)
 		}
 
-	return 0
+		return ListValue{
+			values,
+		}
+	case map[string]interface{}:
+		values := map[string]Value{}
+		for key, value := range v {
+			values[key] = GoToValue(value)
+		}
+
+		return ObjectValue{
+			values,
+		}
+	}
+
+	panic(fmt.Sprintf("unsupported automatic type conversion: %v (%s)", gov, reflect.TypeOf(gov).Name()))
 }
 
 type Value interface {
+	// Type get the type of the value (a ValueType)
 	Type() ValueType
+
+	// String Convert this value to a string fit for human consumption
 	String() string
+
+	// DebugString get a debug string of this value. Used in lists.
+	DebugString() string
+
+	// Equals Check if two values are equal
+	Equals(Value) bool
+
+	// Get a member from the value. An error is returned if the member does not exist
+	Get(string) (Value, error)
 }
 
 type NilValue struct{}
@@ -74,6 +109,18 @@ func (v NilValue) String() string {
 	return "nil"
 }
 
+func (v NilValue) DebugString() string {
+	return v.String()
+}
+
+func (v NilValue) Equals(other Value) bool {
+	return other.Type() == NilValueType
+}
+
+func (v NilValue) Get(key string) (Value, error) {
+	return nil, errors.New("nil has no properties")
+}
+
 type BoolValue bool
 
 func (v BoolValue) Type() ValueType {
@@ -88,6 +135,58 @@ func (v BoolValue) String() string {
 	}
 }
 
+func (v BoolValue) DebugString() string {
+	return v.String()
+}
+
+func (v BoolValue) Equals(other Value) bool {
+	return other.Type() == BoolValueType && bool(other.(BoolValue)) == bool(v)
+}
+
+func (v BoolValue) Get(key string) (Value, error) {
+	return nil, errors.New("booleans have no properties")
+}
+
+// ObjectValue An object with any number of members (key-value pairs)
+type ObjectValue struct {
+	members map[string]Value
+}
+
+func (v ObjectValue) Type() ValueType {
+	return ObjectValueType
+}
+
+func (v ObjectValue) String() string {
+	out := "{"
+	for key, value := range v.members {
+		if out != "{" {
+			out += ", "
+		}
+
+		out += fmt.Sprintf("%q=%s", key, value.String())
+	}
+	out += "}"
+
+	return out
+}
+
+func (v ObjectValue) DebugString() string {
+	return v.String()
+}
+
+func (v ObjectValue) Equals(other Value) bool {
+	// TODO implement object equality check
+	return false
+}
+
+func (v ObjectValue) Get(key string) (Value, error) {
+	if member := v.members[key]; member == nil {
+		return nil, errors.New("no property found with name \"" + key + "\"")
+	} else {
+		return member, nil
+	}
+}
+
 // NumberValue Integer or floating-point values
 type NumberValue float64
 
@@ -101,6 +200,19 @@ func (v NumberValue) String() string {
 	return strconv.FormatFloat(float64(v), 'g', -1, NumberSize)
 }
 
+func (v NumberValue) DebugString() string {
+	return v.String()
+}
+
+func (v NumberValue) Equals(other Value) bool {
+	return other.Type() == NumberValueType && float64(other.(NumberValue)) == float64(v)
+}
+
+func (v NumberValue) Get(key string) (Value, error) {
+	// TODO maybe add standard functions for number values?
+	return nil, errors.New("numbers have no properties")
+}
+
 type StringValue string
 
 func (v StringValue) Type() ValueType {
@@ -111,10 +223,179 @@ func (v StringValue) String() string {
 	return string(v)
 }
 
+func (v StringValue) DebugString() string {
+	return "\"" + v.String() + "\""
+}
+
+func (v StringValue) Equals(other Value) bool {
+	return other.Type() == StringValueType && string(other.(StringValue)) == string(v)
+}
+
+var StringPrototype = map[string]BuiltinFunctionValue{
+	"split": {
+		"split",
+		[]string{"seperator"},
+		func(vm *VM, this Value, m map[string]Value) (Value, error) {
+			str := this.(StringValue).String()
+			sep := m["seperator"].(StringValue).String()
+
+			var out []string
+			tmp := strings.Builder{}
+			for i := 0; i < len(str)-len(sep); i++ {
+				tmp.WriteRune([]rune(str)[i])
+
+				if str[i:i+len(sep)] == sep {
+					out = append(out, tmp.String())
+					tmp.Reset()
+				}
+			}
+
+			return GoToValue(out), nil
+		},
+		nil,
+	},
+}
+
+func (v StringValue) Get(key string) (Value, error) {
+	if prop, ok := StringPrototype[key]; ok {
+		return prop, nil
+	}
+
+	return nil, errors.New(fmt.Sprintf("string has no property \"%s\"", key))
+}
+
+// ListValue a dynamic list of values
+type ListValue struct {
+	items []Value
+}
+
+func (v ListValue) Type() ValueType {
+	return ListValueType
+}
+
+func (v ListValue) String() string {
+	out := "["
+	for i, item := range v.items {
+		if i != 0 {
+			out += ", "
+		}
+		out += item.DebugString()
+	}
+	out += "]"
+
+	return out
+}
+
+func (v ListValue) DebugString() string {
+	return v.String()
+}
+
+func (v ListValue) Equals(other Value) bool {
+	return other.Type() == ListValueType &&
+		slices.Equal(v.items, other.(ListValue).items)
+}
+
+var ListPrototype = map[string]BuiltinFunctionValue{
+	"append": {
+		"append",
+		[]string{"item"},
+		func(_ *VM, this Value, p map[string]Value) (Value, error) {
+			return ListValue{
+				append(this.(ListValue).items, p["item"]),
+			}, nil
+		},
+		nil,
+	},
+	"at": {
+		"at",
+		[]string{"index"},
+		func(_ *VM, this Value, p map[string]Value) (Value, error) {
+			index := int(p["index"].(NumberValue))
+			items := this.(ListValue).items
+
+			if index >= len(items) {
+				return nil, errors.New(fmt.Sprintf("list index %x out of range", index))
+			}
+
+			return items[index], nil
+		},
+		nil,
+	},
+	"length": {
+		"length",
+		[]string{},
+		func(_ *VM, this Value, p map[string]Value) (Value, error) {
+			return NumberValue(len(this.(ListValue).items)), nil
+		},
+		nil,
+	},
+	"map": {
+		"map",
+		[]string{"f"},
+		func(vm *VM, value Value, m map[string]Value) (Value, error) {
+			list := value.(ListValue)
+
+			v := m["f"]
+			var f Value
+			f, ok := v.(FunctionValue)
+			if !ok {
+				f, ok = v.(BuiltinFunctionValue)
+
+				if !ok {
+					return nil, errors.New(fmt.Sprintf("not a function to apply: %s", v))
+				}
+			}
+
+			for i, item := range list.items {
+				var err error
+				list.items[i], err = vm.Call(f, []Value{
+					item,
+				})
+
+				if err != nil {
+					return nil, err
+				}
+			}
+
+			return list, nil
+		},
+		nil,
+	},
+	"reduce": {
+		"reduce",
+		[]string{"f", "start"},
+		func(vm *VM, value Value, m map[string]Value) (Value, error) {
+			list := value.(ListValue)
+			f := m["f"]
+			sum := m["start"]
+
+			for _, v := range list.items {
+				result, err := vm.Call(f, []Value{sum, v})
+				if err != nil {
+					return nil, err
+				}
+				sum = result
+			}
+
+			return sum, nil
+		},
+		nil,
+	},
+}
+
+func (v ListValue) Get(key string) (Value, error) {
+	if prop, ok := ListPrototype[key]; ok {
+		return prop, nil
+	}
+
+	return nil, errors.New(fmt.Sprintf("list has no property \"%s\"", key))
+}
+
 type FunctionValue struct {
 	Name   string
 	Params []string
 	Chunk  *Chunk
+	Parent Value
 }
 
 func (v FunctionValue) Type() ValueType {
@@ -125,10 +406,25 @@ func (v FunctionValue) String() string {
 	return fmt.Sprintf("<function name=%s>", v.Name)
 }
 
+func (v FunctionValue) DebugString() string {
+	return v.String()
+}
+
+func (v FunctionValue) Equals(other Value) bool {
+	return other.Type() == FunctionValueType &&
+		v.Name == other.(FunctionValue).Name &&
+		v.Chunk == other.(FunctionValue).Chunk
+}
+
+func (v FunctionValue) Get(_ string) (Value, error) {
+	return nil, errors.New("functions have no properties")
+}
+
 type BuiltinFunctionValue struct {
 	Name       string
 	Parameters []string
-	F          func(map[string]Value) Value
+	F          func(*VM, Value, map[string]Value) (Value, error)
+	Parent     Value
 }
 
 func (v BuiltinFunctionValue) Type() ValueType {
@@ -139,6 +435,19 @@ func (v BuiltinFunctionValue) String() string {
 	return fmt.Sprintf("<function name=%s builtin>", v.Name)
 }
 
+func (v BuiltinFunctionValue) DebugString() string {
+	return v.String()
+}
+
+func (v BuiltinFunctionValue) Equals(other Value) bool {
+	return other.Type() == BuiltinFunctionValueType &&
+		v.Name == other.(BuiltinFunctionValue).Name
+}
+
+func (v BuiltinFunctionValue) Get(_ string) (Value, error) {
+	return nil, errors.New("functions have no properties")
+}
+
 // VariableValue a value wrapper for variables kept on the stack
 type VariableValue struct {
 	name  string
@@ -157,6 +466,16 @@ func (v VariableValue) String() string {
 	//panic("tried getting string value of a unreachable value")
 }
 
-func (v VariableValue) equals(other VariableValue) bool {
-	return v.name == other.name && v.value == other.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")
 }

core/vm.go

@@ -41,6 +41,8 @@ const (
 	// InstructionGreaterOrEqual pops two from stack, pushes whether the lowest is greater or equal than the highest
 	InstructionGreaterOrEqual
 
+	// InstructionAccessProperty gets a property from a value, and pops it onto the stack
+	InstructionAccessProperty
 	// InstructionCall pops a function object from the stack and begins execution of the chunk
 	InstructionCall
 
@@ -89,6 +91,14 @@ const (
 	// InstructionNil Push a nil literal to the stack
 	InstructionNil
 
+	// InstructionNewList Push a new (empty) list to the stack
+	InstructionNewList
+	// InstructionAppend Append to a list. stack: (... > list > item) => (... > list)
+	InstructionAppend
+	// InstructionFormList Form items on the stack into a list. The 2 bytes after the instructions are the amount of
+	// items to include minus one. (value of 0 => 1 item, value of 1 => 2 items, etc.)
+	InstructionFormList
+
 	// InstructionBreakpoint for debugging purposes
 	InstructionBreakpoint
 )
@@ -161,8 +171,16 @@ func (b Bytecode) String() string {
 		return "AND"
 	case InstructionOr:
 		return "OR"
+	case InstructionFormList:
+		return "FORM_LIST"
 	case InstructionBreakpoint:
 		return "BREAKPOINT"
+	case InstructionNewList:
+		return "NEW_LIST"
+	case InstructionAppend:
+		return "APPEND"
+	case InstructionAccessProperty:
+		return "ACCESS_PROPERTY"
 	}
 	return "UNDEFINED"
 }
@@ -268,18 +286,32 @@ var DefaultGlobals = map[string]Value{
 	"write": BuiltinFunctionValue{
 		"write", // always remember where you come from...
 		[]string{"value"},
-		func(v map[string]Value) Value {
+		func(_ *VM, this Value, v map[string]Value) (Value, error) {
 			println(v["value"].String())
-			return nil
+			return nil, nil
 		},
+		nil,
 	},
 	"print": BuiltinFunctionValue{
 		"print",
 		[]string{"value"},
-		func(v map[string]Value) Value {
+		func(_ *VM, this Value, v map[string]Value) (Value, error) {
 			print(v["value"].String())
-			return nil
+			return nil, nil
 		},
+		nil,
+	},
+	"assert": BuiltinFunctionValue{
+		"assert",
+		[]string{"condition"},
+		func(vm *VM, this Value, params map[string]Value) (Value, error) {
+			if !params["condition"].(BoolValue) {
+				return nil, errors.New("assertion failed")
+			}
+
+			return NilValue{}, nil
+		},
+		nil,
 	},
 }
 
@@ -300,7 +332,7 @@ func NewVM(chunk *Chunk, stackSize Pos, callstackSize Pos) *VM {
 func (vm *VM) Next() bool {
 	switch vm.NextByte() {
 	case InstructionReturn:
-		if vm.call.Current <= 0 {
+		if vm.call.Current == 0 {
 			return false
 		} else {
 			v := vm.stack.Pop()
@@ -351,16 +383,14 @@ func (vm *VM) Next() bool {
 		vm.stack.Push(l / r)
 
 	case InstructionEquals:
-		r := vm.stack.Pop().(NumberValue)
-		l := vm.stack.Pop().(NumberValue)
-
-		vm.stack.Push(BoolValue(l == r))
+		vm.stack.Push(
+			BoolValue(vm.stack.Pop().Equals(vm.stack.Pop())),
+		)
 
 	case InstructionNotEqual:
-		r := vm.stack.Pop().(NumberValue)
-		l := vm.stack.Pop().(NumberValue)
-
-		vm.stack.Push(BoolValue(l != r))
+		vm.stack.Push(
+			BoolValue(!vm.stack.Pop().Equals(vm.stack.Pop())),
+		)
 
 	case InstructionNot:
 		b := vm.stack.Pop().(BoolValue)
@@ -412,7 +442,6 @@ func (vm *VM) Next() bool {
 				scope:       vm.scope,
 			})
 
-			// TODO Fix the variables sometimes being wrongly assigned
 			for i := len(f.Params) - 1; i >= 0; i-- {
 				p := vm.stack.Current - Pos(len(f.Params)) + Pos(i)
 				vm.stack.items[p] = &VariableValue{
@@ -422,6 +451,10 @@ func (vm *VM) Next() bool {
 				}
 			}
 
+			if f.Parent != nil {
+				vm.addVar("this", f.Parent)
+			}
+
 			vm.variableEnd = vm.stack.Current
 
 			vm.chunk = f.Chunk
@@ -433,9 +466,14 @@ func (vm *VM) Next() bool {
 				args[f.Parameters[i]] = vm.stack.Pop()
 			}
 
-			vm.stack.Push(f.F(args))
+			v, err := f.F(vm, f.Parent, args)
+			if err != nil {
+				vm.error(err.Error())
+			}
+
+			vm.stack.Push(v)
 		default:
-			vm.error(fmt.Sprintf("value called is not a function (%s)", v.String()))
+			vm.error(fmt.Sprintf("value called is not a function (%s)", v.DebugString()))
 			return false
 		}
 
@@ -495,6 +533,17 @@ func (vm *VM) Next() bool {
 	case InstructionNil:
 		vm.stack.Push(NilValue{})
 
+	case InstructionFormList:
+
+	case InstructionNewList:
+		vm.stack.Push(ListValue{[]Value{}})
+
+	case InstructionAppend:
+		value := vm.stack.Pop()
+		list := vm.stack.Pop().(ListValue)
+		list.items = append(list.items, value)
+		vm.stack.Push(list)
+
 	case InstructionDescend:
 		vm.descend()
 
@@ -517,6 +566,28 @@ func (vm *VM) Next() bool {
 
 		vm.stack.Push(r, l)
 
+	case InstructionAccessProperty:
+		source := vm.stack.Pop()
+		property := vm.ReadConstant()
+
+		member, err := source.Get(property.(StringValue).String())
+		if err != nil {
+			vm.error(err.Error())
+		}
+
+		// add parent if function with a little switcheroo
+		if member.Type() == FunctionValueType {
+			f := member.(FunctionValue)
+			f.Parent = source
+			member = f
+		} else if member.Type() == BuiltinFunctionValueType {
+			f := member.(BuiltinFunctionValue)
+			f.Parent = source
+			member = f
+		}
+
+		vm.stack.Push(member)
+
 	case InstructionBreakpoint:
 
 	default:
@@ -526,6 +597,52 @@ func (vm *VM) Next() bool {
 	return true
 }
 
+func (vm *VM) Call(v Value, args []Value) (Value, error) {
+	switch f := v.(type) {
+	case FunctionValue:
+		vm.call.Push(Call{
+			chunk:       vm.chunk,
+			ip:          vm.ip,
+			stackEnd:    vm.stack.Current,
+			variableEnd: vm.variableEnd,
+			scope:       vm.scope,
+		})
+
+		for i := 0; i < len(f.Params); i++ {
+			vm.addVar(f.Params[i], args[i])
+		}
+
+		if f.Parent != nil {
+			vm.addVar("this", f.Parent)
+		}
+
+		vm.variableEnd = vm.stack.Current
+
+		vm.chunk = f.Chunk
+		vm.ip = 0
+
+		for vm.chunk.Bytecode[vm.ip] != InstructionReturn && vm.Next() {
+		}
+
+		if vm.HasNext() {
+			vm.Next()
+		}
+
+		return vm.stack.Pop(), nil
+
+	case BuiltinFunctionValue:
+		argies := map[string]Value{}
+
+		for i, arg := range args {
+			argies[f.Parameters[i]] = arg
+		}
+
+		return f.F(vm, f.Parent, argies)
+	}
+
+	return nil, errors.New(fmt.Sprintf("value is not a function (%s)", v.DebugString()))
+}
+
 func (vm *VM) TryNextByte() (Bytecode, error) {
 	if !vm.HasNext() {
 		return 0, errors.New("there are no more instructions")

wasm/wasm.go

@@ -3,11 +3,44 @@
 package main
 
 import (
+	"errors"
 	"log"
 	"neemek.com/anglais/core"
 	"syscall/js"
 )
 
+type JsResolver struct {
+	jsResolver js.Value
+}
+
+func (r *JsResolver) Resolve(name string) (core.Node, error) {
+	jsv := r.jsResolver.Invoke(name)
+
+	if jsv.Type() == js.TypeUndefined {
+		return nil, errors.New("cannot find import with name " + name)
+	}
+
+	if jsv.Type() != js.TypeString {
+		return nil, errors.New("invalid value for source: " + jsv.String())
+	}
+
+	source := jsv.String()
+
+	l := core.NewLexer(source)
+	tokens, err := l.Tokenize()
+	if err != nil {
+		return nil, err
+	}
+
+	p := core.NewParser(tokens)
+	tree, err := p.Parse()
+	if err != nil {
+		return nil, err
+	}
+
+	return tree, nil
+}
+
 func jsError(err error) interface{} {
 	return jsErrorOfString(err.Error())
 }
@@ -22,6 +55,7 @@ func jsErrorOfString(err string) interface{} {
 func run(this js.Value, args []js.Value) interface{} {
 	source := args[0].String()
 	outputHandler := args[1]
+	resolver := args[2]
 	log.Printf("got source: %s", source)
 
 	lexer := core.NewLexer(source)
@@ -45,6 +79,16 @@ func run(this js.Value, args []js.Value) interface{} {
 
 	compiler := core.NewCompiler()
 
+	compiler.SetImportsResolver(&JsResolver{
+		resolver,
+	})
+
+	defer func() {
+		if err := recover(); err != nil {
+			log.Printf("panic recovered: %v", err)
+		}
+	}()
+
 	compiler.Compile(tree)
 
 	log.Printf("Compiled tree (into %i instructions)", len(compiler.Chunk.Bytecode))
@@ -55,19 +99,19 @@ func run(this js.Value, args []js.Value) interface{} {
 	vm.SetGlobal("write", core.BuiltinFunctionValue{
 		Name:       "write",
 		Parameters: []string{"value"},
-		F: func(v map[string]core.Value) core.Value {
+		F: func(vm *core.VM, this core.Value, v map[string]core.Value) (core.Value, error) {
 			log.Printf("Writing value: %s", v["value"].String())
 			outputHandler.Invoke(js.ValueOf(v["value"].String() + "\n"))
-			return nil
+			return nil, nil
 		},
 	})
 	vm.SetGlobal("print", core.BuiltinFunctionValue{
 		Name:       "print",
 		Parameters: []string{"value"},
-		F: func(v map[string]core.Value) core.Value {
+		F: func(vm *core.VM, this core.Value, v map[string]core.Value) (core.Value, error) {
 			log.Printf("Printing value: %s", v["value"].String())
 			outputHandler.Invoke(js.ValueOf(v["value"].String()))
-			return nil
+			return nil, nil
 		},
 	})