Background: In the recent thread help with simplifying program, BillKSmith recommended the use of <Algorithm::Combinatorics>. This uses iterators to go through combinations of data. I love to write terse code so I ended up with (which I did not post in the original thread):
use strict;
use warnings;
use Algorithm::Combinatorics qw(combinations);
my $rep = 5; # should be 100
my @data = 0..$rep;
my $iter = combinations( \@data, 4 );
while( my ( $z, $y, $x, $w ) = @{ $iter->next // last } ) {
next unless $w-2*$x+$y or $x-2*$y+$z;
print "$w, $x, $y, $z\n";
}
My question is about the // last part. I reads nicely like "next or last" but I am aware that this exit from the while loop makes while redundant. I might as well use goto or write
while(1){
my ( $z, $y, $x, $w ) = @{ $iter->next // last };
...
}
What do you think about this use of last here? Is it a nice short way of exiting the loop when the iterator becomes undef when exhausted or is this breaking too much of the loop's structure? Or are there even hidden dangers that I have not spotted?
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