Re: Re: (stephen) Hash Tutorial

[!unlike]

stephen,
I came across this thread, and you post, when looking for some help in doing a diff on the keys between two hashes.

Although code didn't answer my question directly it did give me the insiration to come up with the following:

perl -le '%foo = (1,1, 2,2, 3,3); %bar = (2,2, 3,3); print map { $_ if
+ !$bar{$_} } keys %foo;'

If you run this code you'll see that only "1" get printed.

Not the most robust piece of code ever, but I came up with it off my own back and it does a job for me. So cheers for the insiration!

!unlike

I write my Perl code like how I like my sex: fast and dirty. ;)

[broquaint]

What you want in your snippet there is a grep() not map() as you're filtering out items not applying transforms to them e.g

shell> perl -le '%a = qw/1 1 2 2 3 3/; %b = qw/2 2 3 3/; \
                 print grep !$b{$_}, keys %a'
1

Also note that the map() in your snippet is returning a list of three items - a 1 and two empty strings.
HTH

_________
broquaint

[!unlike]

Thanks broquaint
I realised this just now and was about to post an update. But you beat me to it. :)

!unlike

I write my Perl code like how I like my sex: fast and dirty. ;)