Re: Regex Or Die!

I'm not supposed to use unless.

I'd say you can use it whenever you want :) Even if I mildly agree with PBP for this issue, I loved Perl also because of unless (even if I use it only as statement modifier, another thing that PBP discourages). Continuing on PBP, why don't you simply negate the if?

if (! /^(foo|bar)/) { die "in pain"; }
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Or use the statement modifier (suitable for this one-instruction case)?

die "whatever" unless /^(foo|bar)/;
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Flavio
perl -ple'$_=reverse' <<<ti.xittelop@oivalf

Don't fool yourself.

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Re^2: Regex Or Die! by ChrisCantrall (Sexton) on Sep 27, 2006 at 00:48 UTC
`die "whatever" unless /^(foo\|bar)/;` I like that it's hard to miss a `die` with this method. It's the first word on the line, the `die` jumps out and screams "This condition is important!" Which also means that this style can get distracting if you're doing a lot of sanity checks inline. So, that's a good reason to encapsulate your sanity checks in subroutines. `$user_number = &validate_user_number($input)` is cleaner than `die "Numbers only please." unless ($input =~ /[0-9]+/); $user_number = $input;` [download] Plus, with a subroutine, you can add more checks without making the usage of that sub any harder to understand.	[reply] [d/l] [select]
Re^2: Regex Or Die! by bart (Canon) on Sep 30, 2006 at 15:00 UTC
I agree with frodo72 in favour of `unless`, using `!~` just because you want to avoid `unless`, is a most hidious practice. `!~` is even far more obscure than `unless`, and you should most definitely not start using it for frivolous reasons. Is there something in PBP about it? If it isn't, I'd add a Best Practices rule of my own: Don't use `!~`	[reply] [d/l] [select]