What I mean is when you write a script, and run it, and Perl gives you an error message, it means there is a problem that must be fixed or the script won't run (properly|at all).
Well, you are right in the sense that whenever Perl gives an error message, it stop execution/compilation. But there are many cases where Perl could have continued - and everything would worked as planned. Triple so in the case of warnings. Consider this program: 
    use strict;
    while ($str = <>) {
        print lc $str;
    }

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It won't run, because Perl refuses it to compile. But if you remove the generation of the error message and its subsequent refusal to continue, for instance, by removing the 'use strict;' line, out outcommenting the relevant part in the source of perl, the program runs fine. There's an error message, but the program doesn't contain bugs.

And then there are the numerous, pointless, warning messages: 

    print (1)
    qw /#/
    $foo + $bar

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which you see written as: 
    print +(1)
    qw /\#/
    ($foo || 0) + ($bar || 0)

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just to please 'use warnings'.

In reply to Re^5: On Commenting Out 'use strict;' by Anonymous Monk
in thread On Commenting Out 'use strict;' by Old_Gray_Bear

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