[phobos] D std.bind

[Andrei Alexandrescu]

Jason Spencer wrote:
> ----- Original Message ---- From: Andrei Alexandrescu
> <andrei at erdani.com>
> 
> 
>> I think you're close to the optimal. I'd probably drop function and
>>  write:
>> 
>> auto g1 = int(int b, int c, int d) { return g(2,b,c,d); };
> 
> 
> That actually fails to compile in 2.047: curry.d(13): found '(' when
> expecting '.' following int
> 
> 
>> All things considered, I'm not sure that that's worse than the 
>> arcana:
>> 
>> auto g1 = bind(&g, _1);
>> 
>> ...
>> 
>> All in all, std.bind looks like a direct derivative of Boost's
>> design, which is built to deal with C++'s issues, and does not
>> avail itself of D's advantages.
> 
> It is at least shorter and comprehensible when glancing at it,
> though.  I'm not a great fan of the boost syntax or implementation
> ported to D either, but I also recognize the need for some easy way
> to automate that much boiler plate code.  Maybe I'll futz around and
> see if I can come up with a nice way of doing partial application.
> If I can, could that be considered for inclusion in functional or
> something?

Sure. I suggest you follow the pattern in std.functional of passing 
aliases around instead of the std.bind style. The latter is less 
efficient. Also I think a non-variadic solution (_0 to _9 are abhorrent) 
wouldn't fare too well.

> Either way, I'd politely suggest that bind should either be fixed or
> removed.  I assume it's been broken for 6 months now, and maybe 3
> years, in D 2.0.  Seems a shame to throw away something that at least
> fills a hole for the time being until something better comes along,
> but it may be better to keep confidence in stability up.

Walter wanted to yank it for a long time. I agreed with some reluctance 
(I agree with the pros you mention) but I think it's best to deprecate 
the thing.


Andrei