restructure project

internal/builtins/pow.go

@@ -0,0 +1,34 @@
+package builtins
+
+import (
+	"monkey/internal/object"
+	"monkey/internal/typing"
+)
+
+func pow(x, y int64) int64 {
+	p := int64(1)
+	for y > 0 {
+		if y&1 != 0 {
+			p *= x
+		}
+		y >>= 1
+		x *= x
+	}
+	return p
+}
+
+// Pow ...
+func Pow(args ...object.Object) object.Object {
+	if err := typing.Check(
+		"pow", args,
+		typing.ExactArgs(2),
+		typing.WithTypes(object.INTEGER_OBJ, object.INTEGER_OBJ),
+	); err != nil {
+		return newError(err.Error())
+	}
+
+	x := args[0].(*object.Integer)
+	y := args[1].(*object.Integer)
+	value := pow(x.Value, y.Value)
+	return &object.Integer{Value: value}
+}