From: Trans <transfire@...>
Date: 2008-12-05T00:47:45+09:00
Subject: Re: Enumerable#select used to return actual values



On Dec 4, 9:44 am, Mark Thomas <m...@thomaszone.com> wrote:
> On Nov 29, 10:46 pm, Mike Austin <"mike[nospam]"@mike-austin.com>
> wrote:
>
> > I'm pretty sure select used to use the actual value of the called block,
> > instead of treating it as just a truthy/falsey boolean.  I know this is
> > unconventional, but it's a really nice, compact way of expressing map and
> > filter in one shot, like list comprehension:
>
> > (1..10).select { |a| a * a if a > 5 }
>
> > Was it ever there, or did I just have a dream about it?  It's easy to
> > implement... just wondering.
>
> This is what I do:
>
> (1..10).collect{ |a| a * a if a > 5 }.compact
>
> The only time this doesn't work is when you want to preserve nils in
> your original array.

And that's exactly what I suggested for #compact, to take a block but
faster b/c it's one pass.

T.

> -- Mark.