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Re: scalar dereferencing.

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From:
Larry Wall
Date:
June 17, 2005 12:24
Subject:
Re: scalar dereferencing.
Message ID:
20050617192439.GF817@wall.org
On Fri, Jun 17, 2005 at 03:56:50AM +0800, Autrijus Tang wrote:
: 
:     my $x = 3;
:     my $y = \$x;
:     say $y + 10;
:     $y++;
:     say $y;
:     say $x;
: 
: Currently in Pugs they print:
: 
:     13
:     4
:     3
: 
: Is this sane?  What is the scalar reference's semantics in face of a
: stringification and numification?  I assume that array/hash references
: simply pass on to the things they references to resolve stringify
: and numify, according to S02, but I had not been able to find mentioning
: about scalar refs

I suspect people will find that counterintuitive.  A more consistent
approach might produce

    13
    14
    14

That is, if + deferences automatically, so should ++, such that the
"thingie" pointed to by both $x and $y is what gets incremented,
not a clone of it.  It should take more work than that to get a COW
reference, I suspect.

Larry

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