Yet another stupid mistake #2: my oh my
Stricture helps me catch some typos by requiring predeclaration of variables (e.g. using the lexical my()). But it doesn't warn me about my stupidity. In this month alone, I have been bitten by two episodes of sloppy refactoring, where I left an extra 'my' on an inner block, something like:
my $foo = blah();
...
for (...) {
my $foo = ...;
...
# we lost what we've done to the inner $foo
}
Of course, -w and 'use strict' didn't help me here. -w only warns about the second 'my' if done in the same scope. And so around half an hour were spent chasing these two silent bugs. I guess a critic policy could be written for this sort of thing, e.g. forbidding two lexical declaration inside the same sub. And discipline yourself to keep paragraphs of code relatively short.
A programmer (mostly Perl 5 nowadays).
My CPAN ID: SHARYANTO. I'm sedusedan on perlmonks. My twitter is stevenharyanto (but I don't tweet much). Follow me on github: sharyanto.
There is a policy :)
http://search.cpan.org/~elliotjs/Perl-Critic-1.113/lib/Perl/Critic/Policy/Variables/ProhibitReusedNames.pm
A Perl::Critic policy for this actually exists: Variables::ProhibitReusedNames :)
warnings::unused also catches that :)
Nice to know :)
@Anonymous: not always :)
$ perl -Mwarnings::unused -wE'my $a=1; { my $a=2 } print $a' Unused variable my $a at -e line 1. 1$ perl -Mwarnings::unused -wE'my $a=1; { my $a=2; $a++ } print $a'
1