Re^2: Split a string into items of constant length

Just a minor nitpick that is always worth to repeat, IMHO: $a should not be used as a general purpose variable -- see sort.

Update: (especially for those who didn't like this post) sauoq explained in greater detail the potential issues with using $a and $b as general purpose variables. He also pointed out that, as is well known, in most cases it won't do much harm. However it was apparent that the person I was answering to was not aware of them and the OP appeared to be a newbie. So, in this context, I'm still convinced it was an important circumstance to bring to their knowledge. Sad to notice more than one's mileage does vary...

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Re^3: Split a string into items of constant length by sauoq (Abbot) on Oct 04, 2005 at 11:25 UTC
`$a` should not be used as a general purpose variable It's probably better to explain that rather than refer to a manpage that won't. At least, not very well. Yes, sort uses package variable `$a` and `$b`. It also localizes them. `$ perl -le '$a="foo"; my @n = (3,2,1); print for sort {$a<=>$b} @n; pr +int $a' 1 2 3 foo` [download] It only becomes an issue if you declare them as lexical variables. `$ perl -le 'my $a; my @n = (3,2,1); print for sort {$a<=>$b} @n' Can't use "my $a" in sort comparison at -e line 1.` [download] And the better fix is probably not to avoid `$a` and `$b` but to be explicit in your `sort` blocks and subs by using `$::a` and `$::b` (or `$Foo::a` and `$Foo::b` if you are in package Foo) explicitly. `$ perl -le 'my $a; my @n = (3,2,1); print for sort {$::a<=>$::b} @n;' 1 2 3` [download] That isn't to say avoiding `$a` and `$b` is a bad thing... they are generally lousy variable names anyway. But I often use them in one-liners. So long as you know when and, more importantly, why it can be an issue, there's no harm in it. -sauoq "My two cents aren't worth a dime.";	[reply] [d/l] [select]
Re^4: Split a string into items of constant length by blazar (Canon) on Oct 04, 2005 at 11:56 UTC
That isn't to say avoiding `$a` and `$b` is a bad thing... they are generally lousy variable names anyway. But I often use them in one-liners. Me too. Also in golf/obfu when I want to keep the code strict safe (even if there would be other built in vars available and provided that it's easy to do so), like in this one.	[reply] [d/l] [select]