I know I can use: 
   $byte_length = do { use bytes; length $str };

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with newer Perls. But I need to use that in a script that could be used with $] >= 5.00503 (or maybe even before thanks to some ISPs). So, how do I know when to use it (which versions) and also how to code it -- can't wrap "use bytes" in an eval.

This thread discusses some other methods to detecting the string length. Although I'd rather get direct access like Devel::Peek does instead of counting bytes in a loop.

In reply to Portable string length in bytes by moseley

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