From: dblack@...
Date: 2007-08-14T23:38:30+09:00
Subject: Re: Does an Array#apply make any sense at all?

On Tue, 14 Aug 2007, nikolai.weibull@gmail.com wrote:

> On Aug 14, 2:07 pm, dbl...@rubypal.com wrote:
>> Hi --
>>
>>
>>
>> On Tue, 14 Aug 2007, Robert Klemme wrote:
>>
>>> Your method should be called "apply!" because it's destructive.
>>
>> I could be wrong, but I think the convention (at least in core Ruby)
>> is that ! methods always come in a pair with the non-! version.  I
>> don't think there are any cases where there's just a method called m!
>> where the ! indicates destructiveness (or other "danger"). All the
>> unpaired destructive methods have non-! names.
>
> Ugh.  This was so NOT about whether to call the method Array#apply or
> Array#apply!.

I know -- I was just replying to a tangential point that Robert
raised.

> I just wrote the absolute shortest solution I could
> think of.  I didn't suggest that it was the final version.  Yes,
> seeing as how my definition mutates its target, Array#apply! is the
> appropriate name.

I would still disagree, on the grounds that ! doesn't mean that a
method changes its receiver; it means the method is "dangerous"
(Matz's definition), and that only has meaning in reference to a
non-dangerous but otherwise equivalent method.

> I simply didn't want to clutter the definition
> thusly:
>
> class Array
>  def apply(method)
>    first.send(method, *self[1..-1])
>  end
> end
>
> (which sort of begs the question why we don't have Array#rest ;-)

Good question :-)


David

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