in reply to Another reduce bug?

You're not missing anything. I observe the same bug. The following two variations make the problem disappear.

Using pure perl version of List::Util 

#! perl -slw
use strict;

BEGIN {$List::Util::TESTING_PERL_ONLY = 1};

use List::Util qw[ reduce ];

my $s = 'this is a test';

my @r;
reduce {
    print "$a:$b";
    push @r, [ $a, $b ];
    $b;
} split ' ', $s;

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Or passing an array instead of the split: 

#! perl -slw
use strict;

use List::Util qw[ reduce ];

my $s = 'this is a test';
my @s = split ' ', $s;

my @r;
reduce {
    print "$a:$b";
    push @r, [ $a, $b ];
    $b;
} @s;

[download]
- Miller

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Re^2: Another reduce bug?
by BrowserUk (Patriarch) on Aug 16, 2007 at 02:43 UTC

    Ha! Thanks for the confirmation. It is a strange one. Following on from your use an array solution, I tried the ol' put it in a list context trick--which is probably a erroneous name, but it serves-- and voila. That also fixes it. Maybe an interation between two different optimisations? Time for a perlbug I think. 

    my @r;
reduce{
    print "$a:$b";
    push @r, [ $a, $b ];
    $b;
} () = split ' ', $s;

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    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority".
    In the absence of evidence, opinion is indistinguishable from prejudice.
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[d/l]

      I expect that to make reduce() loop over an empty list and, for me, that is what it does. So, at least in my environment, I don't see how that qualifies as "fixing".

      - tye        

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