[Proposal] Optional function arguments

[ceymard]

function myfunc (arg, [options], callback)
     ...

->

function myfunc (arg, _options, _callback) {
     if (typeof _callback === "undefined") {
          _callback = _options;
          _options = undefined;
     }
}

Or something like that...

This would greatly simplify declaration of functions with optional arguments that some framework use lately (like NodeJS)

[satyr]

Related: https://github.com/jashkenas/coffee-script/issues/1091

Needed:

• syntax
• compilation strategy

[thejh]

@ceymard Why not just void?

function myfunc (arg, [options], callback)
  void

[ceymard]

How does void solve my problem ?

[thejh]

Uh, I misunderstood your proposal, sorry.

[mikeaustin]

Optional parameters without named arguments seems like it could get pretty hairy, no? Personally, I think any new dynamically-typed languages should require named parameters (after the first) - code is about reading, not writing.