Your First Macro

Let's create a class that uses Macroforge's derive macros to automatically generate useful methods.

Creating a Class with Derive Macros

Start by creating a simple User class. We'll use the @derive decorator to automatically generate methods.

Before (Your Code)

/** @derive(Debug, Clone, PartialEq) */
export class User {
  name: string;
  age: number;
  email: string;

  constructor(name: string, age: number, email: string) {
    this.name = name;
    this.age = age;
    this.email = email;
  }
}

After (Generated)

export class User {
  name: string;
  age: number;
  email: string;

  constructor(name: string, age: number, email: string) {
    this.name = name;
    this.age = age;
    this.email = email;
  }

  static toString(value: User): string {
    return userToString(value);
}

  static clone(value: User): User {
    return userClone(value);
}

  static equals(a: User, b: User): boolean {
    return userEquals(a, b);
}
}

export function userToString(value: User): string {const parts: string[] = [];
                        parts.push("name: " + value.name);
                        parts.push("age: " + value.age);
                        parts.push("email: " + value.email);


                        return "User { " + parts.join(", ") + " }";








                }

export function userClone(value: User): User {
                    const cloned = Object.create(Object.getPrototypeOf(value));
                    cloned.name = value.name;
                    cloned.age = value.age;
                    cloned.email = value.email;


                    return cloned;
                }

export function userEquals(a: User, b: User): boolean {
                    if (a === b) return true;
                    return a.name === b.name && a.age === b.age && a.email === b.email;
                }

Using the Generated Methods

TypeScript

const user = new User("Alice", 30, "[email protected]");

// Debug: toString()
console.log(user.toString());
// Output: User { name: Alice, age: 30, email: [email protected] }

// Clone: clone()
const copy = user.clone();
console.log(copy.name); // "Alice"

// Eq: equals()
console.log(user.equals(copy)); // true

const different = new User("Bob", 25, "[email protected]");
console.log(user.equals(different)); // false

Customizing Behavior

You can customize how macros work using field-level decorators. For example, with the Debug macro: