A junior wrote some code like this:
use strict;
use warnings;

our $a = "something";

if($a eq "taste")
{
    print "\nNot equals";
}
elsif($a eq m/ERROR/)
{
    print "\nNot matches regex";
}

[download]

I wasted 15 mins trying to figure out what was wrong at line 6, because PERL told me to look there: 

Use of uninitialized value $_ in pattern match (m//) at wtf.pl line 6.

[download]

Yes, I read that you should look around the block where PERL issues a warning message and not usually at the line number itself, but do understand that in real life the code which resulted in this error message was not so tiny as I have posted, neither were the number of conditions and/or branches... so visual inspection is not always very reliable neither productive..

Any suggestions on how to locate the snippet in error next time I face a similar error ?

For those still wondering, an 'eq' should be '=~'.. oh well..

In reply to Tracking down the line in error or warning by PoorLuzer

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