To the best of my knowledge, use v5.10.1 merely indicates to perl that you'd like to enable all features that exist in v5.10.1 and that your script is not expected to run on older perl versions, or conform to their restrictions and limitations. It cannot be used to "downgrade" a newer perl version to an older one by emulating the old version's behavior.

It is possible to use $^V (aka $PERL_VERSION if you use English;) to check the version of perl you're running on and use different code for different versions, but this is of debatable utility. If you need your code to run on older perl versions, it's best to just stick to constructs they allowed and not use newer features.

In reply to Re: use version confusion by AppleFritter
in thread use version confusion by 1s44c

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