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Re: reduce via ^

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From:
Damian Conway
Date:
October 10, 2001 04:42
Subject:
Re: reduce via ^
Message ID:
200110101142.VAA07353@indy05.csse.monash.edu.au
 
 John observed:

   > I just read Apocalypse and Exegesis 3, and something stuck out at me
   > because of its omission, namely using hyper operators for reduction.
   > 
   > $a ^+= @list;  # should sum the elements of @list
   > 
   > Larry says @a ^+ 1 will replicate the scalar value for all a's, and
   > Damian talks about doing summation with the reduce function without
   > mentioning this compact syntax.
   > 
   > So am I overlooking some obvious reason why this won't work?

No. I expect that this would indeed work.

Note that it's not really a replacement for C<reduce> since it *requires*
the lvalue in order to work. But it is a nice idiom.

Why didn't we mention it in A3/E3.

Well, I suspect Larry didn't mention it because he didn't want to scare
people *too* much. I didn't mention it for a much simpler reason:
because, in the heat of trying to weld together a concise example to
explain of everything Larry had designed, this neat corollary of ^
simply didn't occur to me. ;-)

Damian

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