functions now capture variables :D

core/compiler.go

@@ -587,6 +587,7 @@ func (c *Compiler) compile(tree Node) error {
 			n.yield,
 			c.Chunk,
 			nil,
+			nil,
 		}
 
 		// restore old chunk and ip
@@ -958,6 +959,13 @@ 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])
 	default:
 		return nil, c.error(fmt.Sprintf("impossible to deduce signature of %s", tree.Type()), tree)
 	}

core/parser.go

@@ -1387,9 +1387,15 @@ func (p *Parser) parseSignature() (TypeSignature, error) {
 			in = append(in, sig)
 		}
 
-		out, err := p.parseSignature()
-		if err != nil {
-			return nil, err
+		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{

core/values.go

@@ -603,6 +603,7 @@ type FunctionValue struct {
 	Yield  TypeSignature
 	Chunk  *Chunk
 	Parent Value
+	Scope  *Scope
 }
 
 func (v *FunctionValue) Type() ValueType {
@@ -633,6 +634,7 @@ func (v *FunctionValue) Clone() Value {
 		v.Yield,
 		v.Chunk,
 		v.Parent,
+		v.Scope,
 	}
 }
 

core/vm.go

@@ -698,7 +698,13 @@ func (vm *VM) Next() bool {
 		vm.stack.Pop()
 
 	case InstructionConstant:
-		vm.stack.Push(vm.ReadConstant())
+		c := vm.ReadConstant()
+
+		if c, ok := c.(*FunctionValue); ok {
+			c.Scope = vm.scope
+		}
+
+		vm.stack.Push(c)
 
 	case InstructionAddFloat:
 		r := vm.stack.Pop().(*FloatValue).Number
@@ -840,6 +846,7 @@ func (vm *VM) Next() bool {
 				scope: vm.scope,
 			})
 
+			vm.scope = f.Scope
 			vm.descend()
 
 			for i := len(f.Params) - 1; i >= 0; i-- {
@@ -993,6 +1000,15 @@ func (vm *VM) Next() bool {
 		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:
@@ -1122,7 +1138,7 @@ func (vm *VM) HasNext() bool {
 }
 
 func (vm *VM) GetConstant(id Bytecode) Value {
-	return vm.chunk.Constants[id]
+	return vm.chunk.Constants[id].Clone()
 }
 
 func (vm *VM) ReadConstant() Value {

era3.ang

@@ -1,10 +1,16 @@
+fn counter() -> (fn() -> int) {
+    i := 0
 
-fn double(a: int) -> int {
-    2*a
+    fn() -> int {
+        i = i + 1
+    }
 }
 
-a := 1
+next := counter()
+other := counter()
 
-a = 2
-
-println(double(2) == 4)
+println(next())
+println(next())
+println(other())
+println(other())
+println(next())