Decorator

Example

import { Decorator, TargetKind } from 'decorator';

let transform = decorator({
  [TargetKind.Parameter]: function (type) {
    this.cover(function (arg) {
      if (type === 'uppercase') return arg.toUpperCase();
      else if (type === 'lowercase') return arg.toLowerCase();
      // nothing
    });
  }
});

class A {
  setLastName(@transform('uppercase') name) {
    this.lastName = name;
  }
}

let a = new A();
a.setName('Doe');

console.log(a.lastName); // outputs `DOE`

Note: you must include the decorate library first

Patterns

Agent method	Pattern
ClassAgent#cover()	(A) ⟼ A
ClassAgent#method()	(N) ⟼ MethodAgent
ClassAgent#override()	(A) ⟼ R
ClassAgent#wrap()	(R) ⟼ R
MethodAgent#toProperty()	( ) ⟼ void
ParameterAgent#getMethod()	( ) ⟼ MethodAgent

Order

On method:

class A {
  @cover1()
  @cover2()
  @wrap()
  @cover3()
  method() {

  }
}

Final order:

⟼ cover1(input) ⟼ A
⟼ cover2() ⟼ A
⟼ cover3() ⟼ A
⟼ method() ⟼ R
⟼ wrap()   ⟼ output

With TSD

$ npm install @slietar/decorator
$ tsd link