Writing a code snippet to create a list of filenames with no extensions given a list of filenames with extensions, i ran into some weirdness. When i create the second array using a grep, the orginal array also changes. Whilst i would expect this behavior with map, it suprised me with grep. My only guess is that both variables are the same array, but they are arrays (not array references) so how would that be? 
#!/usr/bin/perl -w
use strict;

my @a = qw(bob.txt bob jack.bmp dave.txt mark);

my @b = grep{$_=(m|^(.*)\.(.*?)$|)?$1:$_}@a;

print join(', ',@a)."\n".join(', ',@b);

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(When code is executed, @a and @b are both contain the values of the grep)

In reply to Grep is changing the original list? by iamcal

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