How to find element exist in the array?

Question

If $client_id doesn't exist in @ping_host it has to pass the if condition, but it only pass when the @ping_host is empty. Am I doing anything wrong?

if ( !grep( $client_id, @ping_host ) ) {
            print "Client Id $client_name doesn't exist \n";
 }

score 3 · Answer 1 · answered Nov 25 '13 at 21:03

It's somewhat inefficient to use grep for this, because it returns all matches in the array, whereas you only care if it has at least one. You could use none for this like:

use List::MoreUtils qw(none);
if(none { $client_id eq $_ } @ping_host) {
    print "Client Id $client_name doesn't exist \n";
}

score 1 · Answer 2 · answered Nov 25 '13 at 20:44

1

First grep parameter should be a test which returns boolean value for each element of @ping_host array,

if ( !grep( $client_id eq $_, @ping_host ) ) {
  print "Client Id $client_name doesn't exist \n";
}

answered Nov 25 '13 at 20:44

mpapec

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is this the same too if (! grep {$_ eq $client_id} @ping_host) – user1595858 Nov 25 '13 at 20:48
@user1595858 yes, these are equivalents. – mpapec Nov 25 '13 at 20:49

How to find element exist in the array?

2 Answers2