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Be careful using splice during array iteration.

Note the subtle bug here:

my @items = ( 0..5 ); my $index = 0; for my $value (@items) { print "testing $value\n"; if ( $value == 1 or $value == 3 ) { print "removed value $value\n"; splice @items, $index, 1; } $index++; }

Values 2 and 4 are never actually tested for; iteration skips them completely!

If you want to iterate over an array removing some items, try something like:

my $index = 0; while ($index <= $#items ) { my $value = $items[$index]; print "testing $value\n"; if ( $value == 1 or $value == 3 ) { print "removed value $value\n"; splice @items, $index, 1; } else { $index++; } }

And, this being Perl I bet there are many other safe iteration/splice approaches... 8-)


In reply to Re: How do I completely remove an element from an array? by jaa
in thread How do I completely remove an element from an array? by vroom

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