restructure project

internal/builtins/pop.go

@@ -0,0 +1,29 @@
+package builtins
+
+import (
+	"monkey/internal/object"
+	"monkey/internal/typing"
+)
+
+// Pop ...
+func Pop(args ...object.Object) object.Object {
+	if err := typing.Check(
+		"pop", args,
+		typing.ExactArgs(1),
+		typing.WithTypes(object.ARRAY_OBJ),
+	); err != nil {
+		return newError(err.Error())
+	}
+
+	arr := args[0].(*object.Array)
+	length := len(arr.Elements)
+
+	if length == 0 {
+		return newError("IndexError: pop from an empty array")
+	}
+
+	element := arr.Elements[length-1]
+	arr.Elements = arr.Elements[:length-1]
+
+	return element
+}