From: Iain Barnett <iainspeed@...>
Date: 2011-03-25T15:02:42+09:00
Subject: Re: shortcut for add unless nil ?


On 24 Mar 2011, at 18:53, Xavier Noria wrote:

> You could do something like this (untested):
> 
>    [a, b, c, d].compact.reduce(:+)
> 
> though whether it is more clear is debatable. I think it reads fine if you're fluent.

That works, thanks, though it starts to feel a bit messy if the array members aren't short vars and/or have square brackets too, as it gets pushed over several lines, and personally I dislike wrapping things with square brackets only to take them off just to use a fold. Whereas:

    a +
    [b,c,d] +
    e +
    f 

would read a lot better in that kind of situation. If it could be done :) The short vars in my example were due to typing laziness, I was thinking more for stuff like this:

    HEADERS = ENV["BLAH_BLAH"] + ENV["BLAH_BLAH_BLAH_BLAH"]

which begins to look unwieldy even with just two fairly long vars:
    
    HEADERS = [ENV["BLAH_BLAH"] + ENV["BLAH_BLAH_BLAH"]].compact.reduce(:+)

but

    HEADERS = ENV["BLAH_BLAH"]           + 
              ENV["BLAH_BLAH_BLAH"]      +
              ENV["BLAH_BLAH_BLAH_BLAH"]

will remain clear even as the vars stack up.

Much appreciated though.

Iain