Even more obvious: 
$ perl -le '$| = 42; print $|;$|--;print $|'
1
0

[download]
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.

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re^3: Poor Perl Idioms Explained (except not really) by QM
in thread Perl Idioms Explained - $|++ by broquaint

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