From: "Jonas Pfenniger (zimbatm)" <jonas@...>
Date: 2011-01-09T09:05:05+09:00
Subject: Re: Best way for Array#find+transform ?

2011/1/8 Anurag Priyam <anurag08priyam@gmail.com>:
>> paths.map{|path| File.join(path, filename)}.select{|name| File.exist?(path)}
>
> Of course, I meant to use name, instead of path in the last section. So:
>
> file = paths.map{|path| File.join(path, filename)}.select{|name|
> File.exist?(name)}

Yes, if you replace #select by #find, then it is correct, you'll get
the same result as my algorithm. But if the result is in the first
entry, then all subsequent paths are unnecessarily joined.

Another version of the algorithm would be:

path = paths.find{|p| File.exist?(File.join(p, filename)) }
if path
  abs_path = File.join(path, filename)
end

In this version, not all the paths are joined, but File.join is called
two times on the resulting path if any.

In any case, it is not a life-or-death issue, but any ways I look at
it, there is still that small imperfection that annoys me :)