Can anyone understand why the two lists output by this test program are different? Note the first word of both lists.

Update: Added the references to the outputs to show they hadn't changed.

Update2: This code won't do anything useful before 5.8.3. 

#! perl -slw
use strict;

my $s = 'the quick brown fox jumps over the lazy dog';

my @wordRefs;

print do{ 
    my $ref = \substr( $s, $-[ 0 ], $+[ 1 ] - $-[ 0 ] );
    push @wordRefs, $ref;
    "$ref : $$ref";
} while $s =~ m[(\S+\s*)]g;

print $/, '---', $/;

print "$_ : $$_" for @wordRefs;

__END__
P:\test>subrefs
LVALUE(0x182caf8) : the
LVALUE(0x1831624) : quick
LVALUE(0x18315d0) : brown
LVALUE(0x1824334) : fox
LVALUE(0x18243f4) : jumps
LVALUE(0x1831660) : over
LVALUE(0x1831678) : the
LVALUE(0x1831690) : lazy
LVALUE(0x18316a8) : dog

---

LVALUE(0x182caf8) : dog
LVALUE(0x1831624) : quick
LVALUE(0x18315d0) : brown
LVALUE(0x1824334) : fox
LVALUE(0x18243f4) : jumps
LVALUE(0x1831660) : over
LVALUE(0x1831678) : the
LVALUE(0x1831690) : lazy
LVALUE(0x18316a8) : dog

[download]

The first list is produced as the references are stacked. The second is produced from those same references. Why are they different?

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algoritm, algorithm on the code side." - tachyon

In reply to Substr ref anomoly (revisited) by BrowserUk

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