+1 for the decorator/function solution. It hardly affects performance in practice, since the resulting wrapped function is a whopping two lines by itself, and engines can optimize that very easily and efficiently. I don't think there needs to be new syntax for it.
One thing I like about JavaScript: its flexibility. I'd say that after ES7 or ES8, there won't be a ton of reason for syntactic additions. From: Jussi Kalliokoski <[email protected]> To: Bucaran <[email protected]> Cc: "[email protected] >> es-discuss" <[email protected]> Date: Tue, 28 Jul 2015 09:43:58 +0300 Subject: Re: self functions 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 <[email protected]> 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) { }) _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
_______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
