perl regular expressions return last matched occurence?

[Dustin D.]

If I attempt to crop a string using regular expressions and the ()
operator for grouping, Perl always seems to return the last match.
For instance, if I have the following:

my $test = "a0\nb0\nc0\na1\nb1\nc1\n";
$test =~ s/.*(\w\d\n).*/$1/s;
print "$test";

The output would be:

c1

I don't understand why it's not a0? Any ideas?

Thanks,
Dustin

 

[Rich]

If I attempt to crop a string using regular expressions and the ()
operator for grouping, Perl always seems to return the last match.
For instance, if I have the following:

my $test = "a0\nb0\nc0\na1\nb1\nc1\n";
$test =~ s/.*(\w\d\n).*/$1/s;
print "$test";

The output would be:

c1

I don't understand why it's not a0? Any ideas?

Thanks,
Dustin

It's all about greed.

Your .* is being greedy and going to the last group of word characters
which is c1. To stop it from being greedy add a ? after the first .*
and it should work the way you expect

Rich