I got bitten by this a few times early on, without necessarially realising that the cause was the closures caused by using lexicals in the code blocks. I just found that using our and/or local meant things worked as I wanted them too.

This is one of the few places where the closure behaviour of Perl's lexicals is distinctly not useful.

I've never seen any mention of this in the POD, though it has come up here and on p5p a few times. I think a documentation patch is a very good idea, though I have my doubts as to the usefulness of a full explanation of the causes and effects. I think a simple "Don't use lexicals in code assertions!" would probably suffice, be more beneficial and less confusing.

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algorithm, algorithm on the code side." - tachyon

In reply to Re^3: Inexplicable uninitialized value when using (?{...}) regexp construct. by BrowserUk
in thread Inexplicable uninitialized value when using (?{...}) regexp construct. by davido

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