Sounds like a bug in your version of Perl - which version are you using? It's my understanding that $a and $b are explicitly excluded from things like the 'used only once' checks for precisely this reason.

For the record, here on 5.005_02 it works as expected - without the error message.

--
<http://www.dave.org.uk>

"Perl makes the fun jobs fun
and the boring jobs bearable" - me

In reply to Re: Sort and related stuff by davorg
in thread Sort and related stuff by leons

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