Support proposed ES Next "::" bind operator

Edit from @DanielRosenwasser: Since this issue was filed, a separate proposal for :: was created called “extensions”.

https://github.com/tc39/proposal-extensions

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It will be great if TypeScript had an implementation of the “::” bind operator of ECMAScript 7. Some examples of this operator and the implementation in ES5: Bind

// ES5
var log = console.log.bind(console);

// ES7
let log = ::console.log;

Call

// ES5
var forEach = Array.prototype.forEach,
    elements = document.querySelectorAll("div");

forEach.call(elements, div => { console.log(div); })

// ES7
let forEach = Array.prototype.forEach,
    elements = document.querySelectorAll("div");

elements::forEach(div => { console.log(div) });

[ref] [more examples]

[igl]

Nicer: https://github.com/mindeavor/es-pipeline-operator

[bterlson]

@mhegazy the story is even more complex - it’s possible “extension” classes (eg. a way to declaratively re-open another class inside a particular scope) would solve many of these use cases as well.

I wouldn’t say effort has stalled - I am still investigating and still want to see one or more of bind operator, bind syntax, pipeline operator, or extension classes in the language. But it will be some time before we get a good sense of the direction and so not implementing in TS for now seems like the best idea.