This will seem trivial to some, but it was very, very annoying to track down in a much larger program. What behavior do you expect from the following program?

use warnings;
use strict;
                                                                      
+               
foo('bar');

my %hash = (bar => 'value');
sub foo { print $hash{+shift} }

[download]

The hash is clearly in scope by the time we get to &foo, but variable declaration occurs at compile while while assignment occurs at runtime. Thus, the output you're likely to see on your console is "Use of uninitialized value in print at ..."

This declaration/assignment mismatch should at least generate a warning, but I'm not sure if it's even possible for the parser to determine. Still, it wasted a fair chunk of my time today :/

Cheers,
Ovid

New address of my CGI Course.

In reply to Mini-rant about 'strict' by Ovid

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