(jeffa) Re: Poor Perl Idioms Explained (except not really)

[jeffa]

An old manager of mine saw $|++ in some of my code and requested i change it to $| = 1. I asked why and he replied that it's better to explicitly set something than to assume it is, say, zero. I know that $| defaults to 0, you know that $| defaults to 0 ... but what if someday the default for $| is instead 1?

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

[robin]

what if someday the default for $| is instead 1?

That's not the problem:

$ perl -le '$| = 1; $|++; print $|++'
1

The problem is that it might confuse someone who doesn't know about this particular piece of DWIMmery.

Update: removed unfunny joke

[QM]

Even more obvious:

$ perl -le '$| = 42; print $|;$|--;print $|'
1
0

So $|++ always sets it to true, and $|-- toggles it. Useful to know, but not obvious, and not consistent. But then DWIMmery is not necessarily consistent.

[jeffa]

I can tell you didn't actually test this.

Actually, i did test it. But you try telling contrary to a manager that won't listen to you. ;) Even if you show him such code. And no ... i don't work for him anymore. :)

Anyways, the point was not what it is now, but what will it be if it changed sometime in the future.