restructure project

internal/object/function.go

@@ -0,0 +1,63 @@
+package object
+
+import (
+	"bytes"
+	"monkey/internal/ast"
+	"strings"
+)
+
+type Function struct {
+	Parameters []*ast.Identifier
+	Body       *ast.BlockStatement
+	Env        *Environment
+}
+
+func (f *Function) Bool() bool {
+	return false
+}
+
+func (f *Function) Type() ObjectType {
+	return FUNCTION_OBJ
+}
+
+func (f *Function) Inspect() string {
+	var out bytes.Buffer
+
+	params := []string{}
+	for _, p := range f.Parameters {
+		params = append(params, p.String())
+	}
+
+	out.WriteString("fn")
+	out.WriteString("(")
+	out.WriteString(strings.Join(params, ", "))
+	out.WriteString(") {\n")
+	out.WriteString(f.Body.String())
+	out.WriteString("\n}")
+
+	return out.String()
+}
+
+func (f *Function) String() string {
+	return f.Inspect()
+}
+
+type ReturnValue struct {
+	Value Object
+}
+
+func (rv *ReturnValue) Bool() bool {
+	return true
+}
+
+func (rv *ReturnValue) Type() ObjectType {
+	return RETURN_VALUE_OBJ
+}
+
+func (rv *ReturnValue) Inspect() string {
+	return rv.Value.Inspect()
+}
+
+func (rv *ReturnValue) String() string {
+	return rv.Inspect()
+}