Greetings all,
I have run across something rather puzzling to me.
This would be easier to illustrate given the code:
#!/usr/bin/perl -w
use strict;
use Dumpvalue;

###how I would normally do it.
my @cells;
for(my $i=0; $i<3; $i++){
    push(@cells,[[],[],[]]);
}

###a different approach.
my @othercells;
@othercells = ([[],[],[]]) x 3;

###lets check shall we?
print "Content-Type:text/html\n\n";
dump_ref(\@cells);
dump_ref(\@othercells);
exit;

###peek under the hood.
sub dump_ref
{
    my $ref = shift;
    my $dumper = new Dumpvalue;
    print "<pre>";
    $dumper->dumpValues($ref);
    print "</pre>";
    print "<br />";
}

[download]
This gives me
0  ARRAY(0x8135f2c)
   0  ARRAY(0x813fb50)
      0  ARRAY(0x812bd00)
           empty array
      1  ARRAY(0x812be2c)
           empty array
      2  ARRAY(0x812bc1c)
           empty array
   1  ARRAY(0x816dc88)
      0  ARRAY(0x812bde4)
           empty array
      1  ARRAY(0x813fb5c)
           empty array
      2  ARRAY(0x813f8ec)
           empty array
   2  ARRAY(0x816dce8)
      0  ARRAY(0x8135efc)
           empty array
      1  ARRAY(0x816dc7c)
           empty array
      2  ARRAY(0x816dcd0)
           empty array

0  ARRAY(0x8135f20)
   0  ARRAY(0x816dd48)
      0  ARRAY(0x813fa48)
           empty array
      1  ARRAY(0x816dcdc)
           empty array
      2  ARRAY(0x816dd30)
           empty array
   1  ARRAY(0x816dd48)
      -> REUSED_ADDRESS
   2  ARRAY(0x816dd48)
      -> REUSED_ADDRESS

[download]
My question is this: Why does the latter method reuse the address of the anonymous array?
My present understanding led me to think that both methodologies would return the same structure (namely the first dumped results), however I was wrong! So could someone please help dispel my obfuscated understanding regarding the latter idiom?
Thanks in advance
-injunjoel

In reply to Comparing two approaches to nested data creation by injunjoel

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