My tests appeared to work for strange reasons. Sorry about that. But you can fix the original without copying the whole environment: 

    local $ENV{BLAH};
    if(  @ARGV  ) {
        $ENV{BLAH}= 42;
    } else {
        delete $ENV{BLAH};
    }

[download]

- tye        

In reply to Re^5: How to localize conditionally? (tias) by tye
in thread How to localize conditionally? by saintmike

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