Deleting array element does not change the array size.

Below I have a simple script that will build an array then delete an
element from it. After deleting the element, the size of the array still
remains the same. I'm a perl newbie and would like to know the correct
way to delete an array element and to obtain the new array size.

use strict;
use warnings;

my @arr = (1, 2, 3);
print @arr; # outputs "123"
my $size = @arr;
print "\nsize=$size\n";
delete $arr[1];
print @arr; # outputs "13"
$size = @arr;
print "\nsize=$size\n"; # this is still 3, why??

Re: Deleting array element does not change the array size.

Sean Nakasone wrote:
> Below I have a simple script that will build an array then delete an
> element from it. After deleting the element, the size of the array still
> remains the same. I'm a perl newbie and would like to know the correct
> way to delete an array element and to obtain the new array size.

from perldoc -f delete:

Note
that deleting array elements in the middle of an
array will not shift the index of the ones after
them down--use splice() for that.

So, you would use splice for that.


>
> use strict;
> use warnings;
>
> my @arr = (1, 2, 3);
> print @arr; # outputs "123"
> my $size = @arr;
> print "\nsize=$size\n";
> delete $arr[1];

splice @arr, 1, 1;

Xho

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Re: Deleting array element does not change the array size.

Sean Nakasone wrote:
> Below I have a simple script that will build an array then delete an
> element from it. After deleting the element, the size of the array
> still remains the same. I'm a perl newbie and would like to know the
> correct way to delete an array element and to obtain the new array
> size.
> use strict;
> use warnings;
>
> my @arr = (1, 2, 3);
> print @arr; # outputs "123"
> my $size = @arr;
> print "\nsize=$size\n";
> delete $arr[1];
> print @arr; # outputs "13"
> $size = @arr;
> print "\nsize=$size\n"; # this is still 3, why??

splice is the right keyword :-)

use strict;
use warnings;
my @arr = (1, 2, 3);
print @arr; # outputs "123"
my $size = @arr;
print "\nsize=$size\n";
#######################
splice @arr,1,1;
#######################
print @arr; # outputs "13"
$size = @arr;
# line above could be: $size = $#arr;
print "\nsize=$size\n"; # this is still 3, why??

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