Suppose I have an array
my @a

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and this array contains some elements that I want to get rid of. Further, I don't know which indices of the array contain the elements I want to expunge, and I want the final array I end up with to contain no empty indices--i.e. I want to ``shorten" the array by 1 everytime I expunge the contents of any of its indices. The way to do this that strikes me as obvious seems inelegant: 
my @new_a;
for my $i (0..$#a){
    push (@new_a, $a[$i]) unless is_unwanted($a[$i]);
}
@a = @new_a;
@new_a = ();

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where is_unwanted is a sub that tests to find out if the contents of an index are of a sort I want to get rid of. Is there a way to do this without creating this extra @new_a array? A (naive) use of splice won't work, since splicing an array changes the identity of the indices with each call. E.g. 
my @a = ("bob", "bob", "martha", "bob");
for my $i (0..$#a){
    splice (@a, $i, 1) if $a[$i] =~ m/bob/;
}
#@a is now ("bob", "martha"), but I don't want any "bob"s;
#also I get harassed about uniniatialized values when I use warnings

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Thanks!

In reply to better array plucking? by young_stu

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