Truth. If you are checking in lots of things exist a hashset might be a
better way to go:
my %hashset = map { ($_ => undef) } (3,1,4,2,9,0);
my $found = exists $hashset{4} || 0;
my $not_found = exists $hashset{10} || 0;
By setting the value of the hash to be undef, you take up less space than
setting it any other value.
On Fri, Aug 19, 2016 at 2:15 PM <wagsworl...@yahoo.com> wrote:
> But does it need to be an array. Rethink into hash and life could be a
> little bit easier...
>
> Wags ;)
> WagsWorld
> Hebrews 4:15
> Ph: 408-914-1341
>
> On Aug 18, 2016, 19:41 -0700, kp...@freenet.de, wrote:
>
> Thanks for all the replies.
> Yes I found List::Util is a useful toolset.
>
>
> On 2016/8/19 10:00, Chas. Owens wrote:
>
> The any function from List::Util will also do what you want.
>
> perldoc List::Util
>
> http://perldoc.perl.org/List/Util.html#any
>
> my $found = any { $_ == 4 } (3, 1, 4, 2, 9, 0); # true
> my $not_found = any { $_ == 10 } (3, 1, 4, 2, 9, 0); # false
>
> Which you want depends on the application. The grep function will
> return a number between 0 and the size of the list and reads the entire
> list. The any function returns the canonical true (a tri-value that
> holds "1", 1, and 1.0) or false (a tri-value that holds "", 0, 0.0)
> values and stops at the first matching value. The canonical false value
> often throws people for a loop as they expect it to be "0" in string
> context, but it is "". You may want to say
>
> my $found = (any { $_ == 10 } (3, 1, 4, 2, 9, 0)) || 0;
>
> to force it to be 0 instead of the canonical false value.
>
>
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