Decorators

Decorators

function log(target: any, key: string, desc: PropertyDescriptor) {
  const orig = desc.value;
  desc.value = function (...args: any[]) {
    console.log(`call ${key}`, args);
    return orig.apply(this, args);
  };
}

class Svc {
  @log
  run(x: number) { return x * 2 }
}

Notes

• Requires "experimentalDecorators": true prior to TS 5; standardized in TS 5.