It's slightly documented in the Camel book on page 598: "Don't undef long strings and arrays if they'll be reused for the same purpose. This helps prevent reallocation when the string or arrayh must be re-extended."

It's reliable till someone changes it... :-)

Perl 5 never GCs a sub's lexicals in the sense we're talking about here. Certainly things can happen to objects that go out of scope, but that's different.

Perl doesn't know when a sub might be called again. It merely assumes it.

In reply to Re: Re: Re: Re: what's faster than .= by TimToady
in thread what's faster than .= by xafwodahs

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