From 34b8ee8a4e898461d350cb015f88708c7bdefdd3 Mon Sep 17 00:00:00 2001
From: brettlangdon <brett@blangdon.com>
Date: Fri, 9 Oct 2015 15:59:20 -0700
Subject: [PATCH] make more progress on compiler/assembler

---
 compiler/compiler.go    | 20 ++++++++++++--------
 compiler/instruction.go | 22 ++++++++++++++++++++++
 compiler/scope.go       | 15 ++++++++++++++-
 3 files changed, 48 insertions(+), 9 deletions(-)
 create mode 100644 compiler/instruction.go

diff --git a/compiler/compiler.go b/compiler/compiler.go
index dfd48a9..c8d4e91 100644
--- a/compiler/compiler.go
+++ b/compiler/compiler.go
@@ -45,28 +45,32 @@ func (compiler *Compiler) exitScope() *Scope {
 
 func (compiler *Compiler) assemble(addNone bool) *gython.CodeObject {
 	if addNone {
-		// compiler.addOp(bytecode.LOAD_CONST)
-		// compiler.addOp(bytecode.RETURN_VALUE)
+		compiler.addOpWithObject(bytecode.LOAD_CONST, gython.None, compiler.currentScope.Constants)
+		compiler.addOp(bytecode.RETURN_VALUE)
 	}
 
 	codeobject := gython.NewCodeObject([]byte{}, []byte{}, 0)
 	return codeobject
 }
 
-func (compiler *Compiler) addOp(op bytecode.Opcode, value gython.Object) bool {
-	// TODO: add `value` object and get oparg
-	oparg := 0
+func (compiler *Compiler) addOp(op bytecode.Opcode) {
+	instr := NewInstruction(op, nil, false)
+	compiler.currentScope.AddInstruction(instr)
+}
+
+func (compiler *Compiler) addOpWithObject(op bytecode.Opcode, value gython.Object, args *gython.Dict) {
+	oparg := args.Length()
+	args.SetItem(oparg, value)
 	instr := NewInstruction(op, oparg, true)
 	compiler.currentScope.AddInstruction(instr)
-	return true
 }
 
 func (compiler *Compiler) visitExpression(expr ast.Expression) bool {
 	switch expr := expr.(type) {
 	case *ast.Num:
-		compiler.addOp(bytecode.LOAD_CONST, expr.Value)
+		compiler.addOpWithObject(bytecode.LOAD_CONST, expr.Value, compiler.currentScope.Constants)
 	case *ast.Name:
-		compiler.addOp(bytecode.STORE_NAME, expr.Identifier)
+		compiler.addOpWithObject(bytecode.STORE_NAME, expr.Identifier, compiler.currentScope.Constants)
 	default:
 		fmt.Println(expr)
 	}
diff --git a/compiler/instruction.go b/compiler/instruction.go
new file mode 100644
index 0000000..48f126c
--- /dev/null
+++ b/compiler/instruction.go
@@ -0,0 +1,22 @@
+package compiler
+
+import (
+	"github.com/brettlangdon/gython/bytecode"
+	"github.com/brettlangdon/gython/gython"
+)
+
+type Instruction struct {
+	Opcode bytecode.Opcode
+	Oparg  *gython.Float
+	Hasarg bool
+	Line   int
+}
+
+func NewInstruction(opcode bytecode.Opcode, oparg *gython.Float, hasarg bool) *Instruction {
+	return &Instruction{
+		Opcode: opcode,
+		Oparg:  oparg,
+		Hasarg: hasarg,
+		Line:   0,
+	}
+}
diff --git a/compiler/scope.go b/compiler/scope.go
index a6bd9c6..1e4de54 100644
--- a/compiler/scope.go
+++ b/compiler/scope.go
@@ -1,12 +1,25 @@
 package compiler
 
+import "github.com/brettlangdon/gython/gython"
+
 type Scope struct {
 	Instructions []*Instruction
+
+	Constants         *gython.Dict
+	Names             *gython.Dict
+	VariableNames     *gython.Dict
+	FreeVariableNames *gython.Dict
+	CellVariableNames *gython.Dict
 }
 
 func NewScope() *Scope {
 	return &Scope{
-		Instructions: make([]*Instruction, 0),
+		Instructions:      make([]*Instruction, 0),
+		Constants:         gython.NewDict(),
+		Names:             gython.NewDict(),
+		VariableNames:     gython.NewDict(),
+		FreeVariableNames: gython.NewDict(),
+		CellVariableNames: gython.NewDict(),
 	}
 }