use strict, strange behavior with single character variables

[johnny_carlos]

Hola Monks,
I've been pulling my hair out for quite a while(more time than I want to admit) trying to figure out why this:

use strict;
$a++;
print $a;

actually prints "1", when it *thought* it should give a compile-time error for not declaring $a. I felt as though I had witnessed the impossibe. For a while there I was questioning my entire existence, and my world was about to collapse since everything I've ever known to be real and true suddenly was not.

I still don't know what the problem is, but my fears were alleviated when I expanded my minimalist test case to this:

use strict;
$aaa++;
print $aaa;

...and this works like it should, dying a horrible, miserable death.

So whats the deal? Anyone know why single character variable names slip through the cracks under the use strict pragma?? Or am I not seeing something?

Thanks!

John

[perlplexer]

$a and $b are special. Look at perldoc -f sort and here

--perlplexer

[grep]

$a and $b are special. They belong to sort (well really they belong to the main package) so they are predeclared.

grep

Unix - where you can throw the manual on the keyboard and get a command

[Zaxo]

See perlvar. $a and $b are package globals sacred to sort. They are exempt from strict, but don't use them. They will cause strange behavior if sort is called.

After Compline,
Zaxo

[Rex(Wrecks)]

$a is a special var used by sort.

From the Camel:
"$a PKGThis var is used by the sort function to hold the first of each pair of values to be compared ($b is used to hold the second). (blah...blah...blah) Because it is a global, it is exempt from use strict ; complaints."

It is a special var and should not really be used outside the sort function.

"Nothing is sure but death and taxes" I say combine the two and its death to all taxes!

[Anonymous Monk]

Oh wow! Cool. I see the light now. Thanks everyone.
John

[particle]

uh...ditto to everyone above. ;)

but seriously... this thread will now be the only place i point people with this question. i've added it to my personal nodelet, where it shall remain in perpetuity, at the ready.

~Particle *accelerates*