Add Error and Method type.

selsl/value/value.go

@@ -2,49 +2,42 @@ package value
 
 import "fmt"
 
+type Members map[string]Value
+
 type Value interface {
-	ID() int
 	Name() string
 	// Proto/type of the value.
 	Type() Type
 	String() string
-	Parent() Value
-	Members() []Value
+	Members() Members
 }
 
 // A type is also a value
 type Type Value
 
-var TypeType Type = NewObject(-1, "Type", nil, nil)
-var ObjectType Type = NewObject(-2, "Object", TypeType, nil)
-var StringType Type = NewObject(-3, "String", ObjectType, nil)
-var IntType Type = NewObject(-4, "Int", ObjectType, nil)
+var TypeType Type = NewObject("Type", nil, nil)
+var ObjectType Type = NewObject("Object", TypeType, nil)
+var ErrorType Type = NewObject("Error", ObjectType, nil)
+var StringType Type = NewObject("String", ObjectType, nil)
+var IntType Type = NewObject("Int", ObjectType, nil)
+var ListType Type = NewObject("List", ObjectType, nil)
+var MethodType Type = NewObject("Method", ObjectType, nil)
 
 type Object struct {
-	id      int
 	name    string
 	typ     Type
-	parent  Value
-	members []Value
+	members Members
 }
 
 func (o Object) String() string {
 	return fmt.Sprintf("%s: %d", o.typ, o.name)
 }
 
-func (o Object) ID() int {
-	return o.id
-}
-
 func (o Object) Name() string {
 	return o.name
 }
 
-func (o Object) Parent() Value {
-	return o.parent
-}
-
-func (o Object) Members() []Value {
+func (o Object) Members() Members {
 	return o.members
 }
 
@@ -52,11 +45,22 @@ func (o Object) Type() Type {
 	return o.typ
 }
 
-func NewObject(id int, name string, typ Type,
-	parent Value, members ...Value) Object {
-	return Object{
-		id: id, name: name, typ: typ, parent: parent, members: members,
-	}
+func NewObject(name string, typ Type, members Members) Object {
+	return Object{name: name, typ: typ, members: members}
+}
+
+type Error struct {
+	Object
+	Value error
+}
+
+func (s Error) String() string {
+	return fmt.Sprintf("%w", s.Value)
+}
+
+func NewError(name string, members Members, value error) Error {
+	return Error{Object: NewObject(name, ErrorType, members),
+		Value: value}
 }
 
 type String struct {
@@ -68,9 +72,8 @@ func (s String) String() string {
 	return s.Value
 }
 
-func NewString(value string, id int, name string,
-	parent Value, members ...Value) String {
-	return String{Object: NewObject(id, name, StringType, parent, members...),
+func NewString(name string, members Members, value string) String {
+	return String{Object: NewObject(name, StringType, members),
 		Value: value}
 }
 
@@ -79,9 +82,8 @@ type Int struct {
 	Value int64
 }
 
-func NewInt(value int64, id int, name string,
-	parent Value, members ...Value) Int {
-	return Int{Object: NewObject(id, name, IntType, parent, members...),
+func NewInt(name string, members Members, value int64) Int {
+	return Int{Object: NewObject(name, IntType, members),
 		Value: value}
 }
 
@@ -91,15 +93,31 @@ func (i Int) String() string {
 
 type List struct {
 	Object
+	Value []Value
 }
 
-func NewList(value int64, id int, name string,
-	parent Value, members ...Value) List {
-	return List{Object: NewObject(id, name, IntType, parent, members...)}
+func NewList(name string, members Members, value ...Value) List {
+	return List{Object: NewObject(name, ListType, members),
+		Value: value}
 }
 
 func (l List) String() string {
-	return fmt.Sprintf("[%v]", l.members)
+	return fmt.Sprintf("[%v]", l.Value)
+}
+
+type Method struct {
+	Object
+	Value func(env Value, self Value, args ...Value) List
+}
+
+func NewMethod(name string, members Members,
+	value func(env Value, self Value, args ...Value) List) Method {
+	return Method{Object: NewObject(name, MethodType, members),
+		Value: value}
+}
+
+func (m Method) String() string {
+	return fmt.Sprintf("Method: %s", m.Name)
 }
 
 var _ Value = String{}