Thanks. This is really interesting. I thought under "normal" circumstances memory allocation for variables was fairly fixed and persistent for PERL and was the reason that 'referencing' works. Perhaps a little knowledge is truely dangerous but I have to push through to turn a little into a little-more, so thanks for the input. Does CV stand for "Code Value"? I found that in 'perlguts' which was pretty heavy reading!

Musings... It seems to me that it is fairly reasonable for a user to want to know if an element of an array or hash 'exists'. Exists could return more than a binary choice and the user could be expected to test the returned value to make sure it is what they wanted. I am guessing that a fairly large portion of PERL code includes arrays and hashes, so predictable results in this area now and in the future seems important. I wonder what code may break in the future and indeed where I might have used it previously and erroneously! The warning certainly made me stop but I needed the why and the guidance on what to do instead.

Thanks again to you and the other contributors.

In reply to Re^2: Using exists to check element in array by david
in thread Using exists to check element in array by david

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