If you do a search on CLPM you'll find this comes up semi-regularly, and I bet there are even a few threads here at the monastery too.

Contrary to the many opinions stated here it is actually NOT localizing the variable. This should be obvious because strict doesnt get mad, and there is no curly brace to indicate a scoped block, and furthermore modifiers operate in the scope they are used and do not create a scope. Instead its reiniting it each time.

What happens is that on the last call to the for (the one where the for has now exhausted the array or more generally evaluated as finished) the my part of the statement is STILL being executed, and thus causing the variable to go to undef.

BTW: Sean in future try to be a bit more careful about the term "null", its meaning is overloaded in the CS world and can lead to confusion. Perl has no "NULL" but it does have undef and no they arent the same.

HTH, and when you do your search youll see that I asked this question a long time ago on CLPM too. :-)

Oh and the moral is that you shouldnt mix lexical declaration with modifiers.

Yves / DeMerphq
---
Writing a good benchmark isnt as easy as it might look.

In reply to Re: 'my' headache...why doesn't this work? by demerphq
in thread 'my' headache...why doesn't this work? by S_Shrum

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