> > I'm also very new to Perl and wrote a long and newbyish script
that
> > does exactly what the Unix command "sort FILENAME | uniq"
> does just to
> > see how it can be done.
>
> How long? Because you can do that on one line in perl. :-)
Hi John (we're not worthy - Wayne's World) ;-)
I've just come back to your post above (30/05/05) and I've tried to
get the internal workings of the code to agree with my brain. Please
help!
> perl -e'print sort grep !$seen{$_}++, <>' FILENAME
Initially I thought you were creating a hashref(?) key with every line
of input, if unique. But I cannot access the keys using the hashref
(below) so there is something else at work here.
for $key_v (keys %{$seen}) {
print "$key_v\n";
}
This returns nothing when used with the above code in a script (code
posted at request). Sorry in advance if I've made newbie mistake but
please explain how !$seen{$_}++ knows what was used before.
PS Will the Perl Cookbook have examples to common tools such as this?
What does everyone think of the book - very helpful?
TIA
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