He posted code that works,

Err, actually, he didn't. See dvergin's post.

I don't see what's so bad about teaching him to do it better (as opposed to at all). map and grep aren't immediately intuitive unless you are already seeped in lisp.

That's why I told him to take a look at map and grep (implying, "Read the documentation"). I am not 'seeped in Lisp'. In fact, I have just started learning some Common Lisp, yet I've been using map and grep in Perl for quite some time now. I assume he's intelligent enough to understand the definition of grep:

    grep - locate elements in a list test true against a given criterion
  

    my @matches = grep { ... } keys %friends
[download]

Why not just tell him to put the conditional into a grep statement and it will spit out the right hashes?

Because he can deduce that from reading the documentation on grep. One of Perl's great resources is its extensive documentation. Learning to read the documentation is a good thing, in my opinion.

As an added bonus, less people will think that you are a grumpy loser.

So I'm a grumpy loser now?

[ ar0n -- want job (boston) ]