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Re^2: changing the position of an element in an array

by nobull (Friar)
on Nov 17, 2005 at 17:48 UTC ( #509497=note: print w/replies, xml ) Need Help??


in reply to Re: changing the position of an element in an array
in thread changing the position of an element in an array

Actually a simple splice/push will not change the position of an element in an array, it will create a new element that comtains a copy of the value from the old of element.
my @array = ( 'foo', 'bar', 'baz' ); my ($pos) = grep { $array[$_] eq 'bar' } 0..$#array; my $ref_to_element = \$array[$pos]; push (@array, splice(@array, $pos, 1)); print "@array\n"; # Prints 'foo baz bar' $$ref_to_element = 'zap'; print "@array\n"; # Still prints 'foo baz bar'

Had $array[1] been moved to the end of the array then $$ref_to_element would point to $array[2] after the move.

Admittedly, this is usually not an issue.

On the rare occasions when you really want to move elements of an array use Array::Splice. In the above example you would use push_aliases() in place of the built-in push().

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