Re: Perl OO Lint

I don't see do_the_other_thing could have been executed because of the typo. I get, as I should,

Can't locate object method "caught" via package "My::Excpetion::Thingy
+" (perhaps you forgot to load "My::Excpetion::Thingy"?) at script.pl 
+line 8.
[download]

True, it's a runtime error, but that's necessary since functions can be loaded at any time (including through AUTOLOAD) and @ISA can change at any time. Perl has no way of knowing at compile-time whether My::Excpetion::Thingy->caught will be valid any or all times that statement will be executed.

For example, I sometimes do:

if ($@) {
   require Carp;
   Carp::croak(...);
}
[download]

Carp::croak doesn't exist until the require is executed, which is only executed at run-time when the exception occurs. A compile-time check would think this is an error. However, I'll cede that it could be useful for lint to give an (overridable) *warning*.

Comment on Re: Perl OO Lint Select or Download Code

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Re^2: Perl OO Lint by jffry (Hermit) on Mar 13, 2006 at 21:23 UTC
Oopsie! Now I see why I wasn't getting the "Can't locate object method...via package..." error. Here is the actual code with names changed to protect the innocent (i.e. me). `eval { $lock->create() }; if (my $exception = My::Execption::Lock::Exists->caught()) { while ($lock->query()) { sleep 180; } exit 0; } die $@ if $@;` [download] Because my `if ()` was always false due to a mispelling, I was just dieing with the prior eval error message, thus supressing the "missing object method" error message. Egads! My shame for all Perl monks to see.	[reply] [d/l] [select]
Re^3: Perl OO Lint by ikegami (Patriarch) on Mar 13, 2006 at 23:13 UTC
What are you talking about? That code still gives the `Can't locate object method "caught" via package "My::Execption::Lock::Exists" (perhaps you forgot to load "My::Execption::Lock::Exists"?)` error message. The `if` is never false (as you say) or even true, since `perl` dies from the type before the `if` expression gets completely evaluated. Similarly, the `die` is never reached, since the `if` encountered a fatal error. I suspect the `if` was within `eval`'s block.	[reply] [d/l] [select]
Re^4: Perl OO Lint by jffry (Hermit) on Mar 14, 2006 at 18:05 UTC
I see what you mean. Well, damn. I have modified the code so much now that I don't have time to break it and go back to find out exactly what was going on. However, in that same program, I *used* to have an END{} subroutine that dealt with the same object. Like this: `eval { $lock->remove() }; if ($@) { if (my $exception = My::Exception::Lock::NotFound->caught()) { warn $exception; } else { die $@; } }` [download] Maybe that had something to do with why I wasn't getting the object-method-not-found error?	[reply] [d/l]