add tuple, none, and dict

gython/dict.go

@@ -0,0 +1,31 @@
+package gython
+
+import "fmt"
+
+type Dict struct {
+	values map[Object]Object
+}
+
+func NewDict() *Dict {
+	return &Dict{
+		values: make(map[Object]Object, 0),
+	}
+}
+
+func (dict *Dict) object() {}
+
+func (dict *Dict) Length() *Float {
+	return NewFloat(float64(len(dict.values)))
+}
+
+func (dict *Dict) GetItem(key Object) (Object, error) {
+	value, exists := dict.values[key]
+	if exists == false {
+		return nil, fmt.Errorf("Key error: %#v", key)
+	}
+	return value, nil
+}
+
+func (dict *Dict) SetItem(key Object, value Object) {
+	dict.values[key] = value
+}

gython/none.go

@@ -0,0 +1,7 @@
+package gython
+
+type _None struct{}
+
+func (none *_None) object() {}
+
+var None *_None = &_None{}

gython/tuple.go

@@ -1,10 +1,17 @@
 package gython
 
 type Tuple struct {
+	length *Float
+	values []Object
 }
 
-func (tuple *Tuple) object() {}
-
-func NewTuple() *Tuple {
-	return &Tuple{}
+func NewTuple(values ...Object) *Tuple {
+	return &Tuple{
+		length: NewFloat(float64(len(values))),
+		values: values,
+	}
 }
+
+func (tuple *Tuple) object()          {}
+func (tuple *Tuple) Length() *Float   { return tuple.length }
+func (tuple *Tuple) Values() []Object { return tuple.values }