From: David Alan Black <dblack@...>
Date: 2002-06-22T08:58:02+09:00
Subject: Re: Looking for the Ruby way for the following

Hello --

On Sat, 22 Jun 2002, Austin Ziegler wrote:

> On Sat, 22 Jun 2002 06:52:05 +0900, David Alan Black wrote:
> > On Sat, 22 Jun 2002, Austin Ziegler wrote:
> >> Why not use #inject()? It seems like it would be the natural
> >> choice in this case.
> > I confess I am #inject-ly challenged. Can you show how this would
> > be done?
>
> I believe that it would be something like (adapted from the Pickaxe
> book):
>
> file_list.inject(0) do
>    |fn_width, fn| fn_width = [File.basename(fn).size, fn_width].max
> end
> fn_width += 1;
>
> I suspect that the map solution you provided earlier is cleaner, and
> you may need to do the appropriate #inject() mixin (p102 of the
> Pickaxe book) if you don't have 1.7 (I think that's when #inject()
> was added).

You could wed the cleanness of #map to the #inject version -- you'd
mainly just want to rewrite it so that you were using the return value
of the call to #inject, rather than relying on the side-effect of
fn_width being incremented.  (Note that with the above version you'd
also have to initialize fn_width beforehand.)

So, you could do something like:

  biggest = file_list.inject(0) {|fn_width,fn|
    fn_width = [File.basename(fn).size,fn_width].max
  } + 1


David

-- 
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav