self functions

[Jussi Kalliokoski]

For classes, you can use decorators [1][1], if they eventually get in in
the language (just one extra symbol):

```JS
function self (object, name, descriptor) {
  var original = descriptor.value;
  return {
    ...descriptor,
    value (...args) {
      original.apply(this, args);
      return this;
    },
  };
}

class Foo {
  constructor () {
    this.x = 0;
  }

  @self
  method () {
    this.x++;
  }
}

console.log(new Foo().method().x) // 1
```

for ES5 style "classes", you can just use functions (2 extra symbols):

```JS
function self (original) {
  return function (...args) {
    original.apply(this, args);
    return this;
  };
}

function Foo () {
  this.x = 0;
}

Foo.prototype.method = self(function () {
  this.x++;
});

console.log(new Foo().method().x) // 1
```

[1]: https://github.com/wycats/javascript-decorators

On Tue, Jul 28, 2015 at 5:06 AM, Bucaran <jbucaran at me.com> wrote:

> Add a `self` decorator to functions that makes them return `this` by
> default.
>
>                 export function self myMethod () {
>                         // return this by default
>                 }
>
> This decorator could be used to make any function bound to the current
> scope `this` as well so:
>
>                 func(function self () { // this is bound to my dad’s scope
> })
>
> Would be roughly equivalent to:
>
>                 func(() => { // this is bound to my dad’s scope })
>
> Although I personally would favor the arrow function syntax, the `self`
> decorator could be
> used to optimize binding generators, so instead of:
>
>                 func(function* () { }.bind(this))
>
> One could write:
>
>                 func(function self* () { })
>
> Similary it could be used in promise handlers, so instead of:
>
>                 new Promise(function (resolve, reject) { }.bind(this))
>
> One could write:
>
>                 new Promise(function self (resolve, reject) { })
>
> It would be even sweeter if you didn’t need to specify the keyword
> function when writing `self` functions:
>
>                 new Promise(self (resolve, reject) { })
> _______________________________________________
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>
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