counter for each regex match.

[tty1x]

I am trying to increase the $count variable by 1 whenever any line in the opened file contains the word Mailto:

However, I kept receiving use of uninitialised value $count error and a long string of numbers at the end as the result.

my @email = <OPENFILE>;
close OPENFILE;

my $count;

foreach my $email (@email){

    if ($email =~ /mailto:/) {
    $count += 1;

    }

    print $count; # error here
}

[davido]

$count's initial state is "undef", or undefined. It doesn't get incremented until the first time that "mailto:" shows up in your input file. Yet you print its value on each iteration.

So imagine the first line of your file is, "More pizza please!". The regex obviously won't match, and so $count won't be incremented. So when you print $count's value, it is still 'undef'.

Either initialize it with a value right where you're declaring $count, or move it outside of the foreach loop, or put an "if defined $count" suffix at the end of your print statement.

[tty1x]

Thanks for the explanation. Moving the print statement out of the for loop did the trick. Elementary mistake =/

[Laurent_R]

However, I kept receiving use of uninitialized value $count error and a long string of numbers at the end as the result.

From your own description of the problem, the main point is to move the print statement outside of the while loop, so that it gets executed only once after you have finished looping on the input.

Initializing $count to 0 when you declare it is slightly less important, but it will avoid the "uninitialized value" warning in the case where nothing was matched in your while loop.

[kcott]

G'day tty1x,

Changing my $count; to my $count = 0; should fix your "uninitialised value" problems.

[Aside: you can write ++$count; instead of $count += 1;]

[tty1x]

Thanks for the  ++$count; tip :)