array builtins

object/array.go

@@ -49,3 +49,31 @@ func (ao *Array) Equal(other Object) bool {
 	}
 	return false
 }
+func (ao *Array) Copy() *Array {
+	elements := make([]Object, len(ao.Elements))
+	for i, e := range ao.Elements {
+		elements[i] = e
+	}
+	return &Array{Elements: elements}
+}
+
+func (ao *Array) Reverse() {
+	for i, j := 0, len(ao.Elements)-1; i < j; i, j = i+1, j-1 {
+		ao.Elements[i], ao.Elements[j] = ao.Elements[j], ao.Elements[i]
+	}
+}
+
+func (ao *Array) Len() int {
+	return len(ao.Elements)
+}
+
+func (ao *Array) Swap(i, j int) {
+	ao.Elements[i], ao.Elements[j] = ao.Elements[j], ao.Elements[i]
+}
+
+func (ao *Array) Less(i, j int) bool {
+	if cmp, ok := ao.Elements[i].(Comparable); ok {
+		return cmp.Less(ao.Elements[j])
+	}
+	return false
+}