Re: splicing and empty rows

[Dave O <cxreg pobox com>]

On Sat, 13 Dec 2003, muppet wrote:

> you actually need to do this:
>
>    sub del_user {
>        my $bywhat = shift;
>        for (0   {$UserList->{'data'}}-1) {
>            if ($UserList->{data}[$_][1] eq $bywhat) {
>                splice @{$UserList->{'data'}}, $_, 1;
>                last; # stop!
>            }
>        }
>        update_busers();
>    }
>
> in general, if you need to modify the list while traversing it, and may
> be removing elements, either traverse it from back to front, or start
> over after every modification.

Another safe way to do this is to back up every time you splice one out,
ie:

    sub del_user {
        my $bywhat = shift;

        my $n = 0;
        while($n <= $#{$UserList->{'data'}}) {
            if ($UserList->{data}[$_][1] eq $bywhat) {
                splice @{$UserList->{'data'}}, $_, 1;
                $n--;
            }
            $n++;
        }
        update_busers();
    }

It allows you to make a full iteration each time through no matter how
many are removed and wont skip or auto-vivify anything :-)  HTH

        Dave