I haven't seen it mentioned yet, but this is documented in perlsub. See the "Subroutine Attributes" section for all the gory details.

Update: oops, I just noticed from the OP:

I've read perldoc perlsub and perldoc attributes

Apologies for not reading the entire post.

In reply to Re: Subs with 'extra stuff'? by revdiablo
in thread Subs with 'extra stuff'? by rvosa

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