Need help !

lonewolf28 has asked for the wisdom of the Perl Monks concerning the following question:

Hi I have a piece of code, when a no is passed twice it will just print out saying the no is called twice. But unfortunately it's not working as intended. Any thoughts ? Thanks

{ 
  my $last = 5;
   sub do_stuff {
       my $arg = @_;
         if ( $arg == $last ) {
             print "You called me twice in a row with $arg\n";
         }
     $last = $arg;
    }
}
do_stuff($_) for 0..5;
[download]

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Re: Need help ! by toolic (Bishop) on Dec 22, 2014 at 00:29 UTC
my $arg = @_; That evaluates the `@_` array in scalar context and assigns the number of elements in the array (which is always 1 in your code) to the `$arg` variable. You likely want: `my ($arg) = @_;` [download] How do I compose an effective node title? I came to this conclusion quickly using print (Tip #2 from the Basic debugging checklist)	[reply] [d/l] [select]
Re: Need help ! by BillKSmith (Monsignor) on Dec 22, 2014 at 14:10 UTC
You can use the 'state' feature' (refer: perldoc perlfunc) rather than the extra block to limit the scope of $last. `use feature 'state'; sub do_stuff { state $last=999; my ($arg) = @_; if ( $arg == $last ) { print "You called me twice in a row with $arg\n"; } $last = $arg; } do_stuff($_) for 0..5,5;` [download] Bill	[reply] [d/l]