Well, maybe ive completely missed the point but implementing a subroutine that keeps its state just seems to be a more complex way of saying that you need static variables. And adding static variables to a subroutine is easy. Just put the subroutine inside an anonymous block, along with lexical declarations for the vars you need to be static and away you go... 
#normal sub
sub foo { 
  return join ("#",@_);
}

{ #Anon block for static vars to live in.
  my $join="-";
  sub bar {
    my $ret=join($join,@_);
    $join=($join eq "-") ? ":" : "-";
    return $ret;
  } 

} # End static block

print foo(1..10),"\n";
print foo(1..10),"\n";
print bar(1..10),"\n";
print bar(1..10),"\n";
print bar(1..10),"\n";
__END__
1#2#3#4#5#6#7#8#9#10
1#2#3#4#5#6#7#8#9#10
1-2-3-4-5-6-7-8-9-10
1:2:3:4:5:6:7:8:9:10
1-2-3-4-5-6-7-8-9-10

[download]
Hope thats what you needed...

:-)

PS: If memory serves me right I believe that the anon block should become a BEGIN block under some circumstances (mod_perl maybe?). I seem to recall something by tye on the matter but I dont recall the details, and I cant find the post in question.

Yves / DeMerphq
---
Writing a good benchmark isnt as easy as it might look.

In reply to Re: A metaclosure? (use static vars) by demerphq
in thread A metaclosure? Howto? by PetaMem

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