what are the lowercase qw/stderr stdin stdout/ for
They're deprecated aliases for STDERR etc.
What do the _<-ones mean
They're for the debugger; see perldebguts.pod for the gory details
precisely when and where the destructor is used
No idea, but the destructor itself is a NOOP.

Dave.

In reply to Re: keys %:: by dave_the_m
in thread keys %:: by blazar

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