Rest arguments

[RealyUniqueName]

Closed in favor of #9961

Implements rest arguments as an abstract over targets native corresponding features.
Closes #7306
Softly deprecates haxe.extern.Rest (no warning for now).

• js
• python
• php
• flash
• cpp
• eval
• lua
• java
• cs
• jvm
• neko

[RealyUniqueName]

@jdonaldson Could you please add a lua implementation?

[Gama11]

to Iterable<T> for static extension support might be nice?

[RealyUniqueName]

No, because it's not compatible with Iterable.
The only thing we can to is adding @:to Iterable

[Gama11]

Hm... but it has iterator()?

[RealyUniqueName]

But it only exists at compile time, while Iterable needs iterator to exist at run time.

[jdonaldson]

Looks like a good start... I got things working for Lua in your test cases.

I think we'll need to add some more restrictions for Rest.... here's some things that are possible, but add a lot of complications to support:

1. Returning a Rest type might need special behavior
2. Passing a Rest type as a dynamic argument.

These should probably be restricted, with a helpful compiler message:

1. Passing a Rest type as an argument before other standard arguments.
2. Passing two or more Rest types

I'm not handling any of these cases yet

[RealyUniqueName]

1. Passing a Rest type as an argument before other standard arguments.
2. Passing two or more Rest types

These are handled by the compiler

[jdonaldson]

1. Passing a Rest type as an argument before other standard arguments.
2. Passing two or more Rest types

These are handled by the compiler

There's not a very clear/explicit error message for these cases...

function rest(r:Rest<Int>, o :Int){
  return o;
}
[...]
var r = rest(3, 2, 1, 0);

or

function rest(r:Rest<Int>, o : Rest<Int>){
  trace(r + " is the value for r");
  return o;
}

Gives:

Main.hx|8 col 16 error| Int should be haxe.Rest<Int>
Main.hx|8 col 16 error| For function argument 'r'

[RealyUniqueName]

There's not a very clear/explicit error message for these cases...

Looks like it's only checked for fields. Will add for local functions too.

[Aurel300]

Spaces -> Tabs again, to be consistent with the stdlib.

[Gama11]

Or just run haxe-formatter over it, there's other formatting issues too. :D

[jdonaldson]

FWIW I added haxe-formatter to this vim plugin : vim-autoformat/vim-autoformat#297

I have it set to autorun when I open a haxe file now.

[jdonaldson]

Should we support returning a Rest argument? I added a breaking test for it.

[nadako]

So... does this support calling rest-argument functions by passing Array (or something that can be created from one) as the rest argument? (i.e. exec(a, b, myRestArgs)). This would be required for such a feature because we have inheritance and super calls (also constructors).

[RealyUniqueName]

So... does this support calling rest-argument functions by passing Array (or something that can be created from one) as the rest argument?

Not yet. I have to figure out inlining for this case first. Or disable inlining functions with rest args completely.

[Simn]

This PR will need an update.

Also, we have to stop randomly stopping to work on things like these.

[RealyUniqueName]

This was not planned and I've started this because I thought it wouldn't take a lot of effort, but it turned out I was wrong, so I moved back to planned tasks.

Main issue is an absence of syntax for passing a collection as rest arguments (e.g. callWithRest(...args))

[ALANVF]

Curious why Neko isn't supported so far. It supports variadic functions and dynamic function application, no?

[RealyUniqueName]

Closed in favor of #9961