This got me thinking - it's one of those timtowtdi thingies, but I thought this solution was quite nice - to begin with - look at this 
# First, but @items into a hash instead though...
my @array = qw(dog cat cow horse donkey chicken);
my %items = qw(cat 1 donkey 1);

# this is weird.. if this is true
print "\$array[-4] = $array[-4]\n";

for (1..@array) {
  splice(@array, -$_, 1) if $items{ $array[-$_] };
}

# and this is true
print "\$array[-4] = $array[-4]\n";

# how come this is right???
print join ', ',@array, "\n";

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And then I thought about it. Hang on. The array's getting spliced each time a match is made, so an index of -$_ would skip elements (ie $array[-4] before is 'cow', after, it's 'dog', which is expected, but... Weird thing is, it doesn't look like it should work. Anyone got any idea why this works when I think it shouldn't???

err

cLive ;-)

In reply to (cLive ;-) Re: Reducing array by cLive ;-)
in thread Reducing array by hotshot

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