Question

I have a simple program where the user can enter a string.
After this the user can enter a regex. I need the string to be compared against this regex.

The following code do not work – the regex always fails.

And I know that its maybe because I am comparing a string with a string and not a string with a regex.

But how would you do this?

while(1){
    print "Enter a string: ";
    $input = <>;
    print "\nEnter a regex and see if it matches the string: ";
    $regex = <>;

    if($input =~ $regex){
        print "\nThe regex $regex matched the string $input\n\n";
    }
}

Answer 1

You need to use a //, m//, or s/// — but you can specify a variable as the pattern.

if ($input =~ /$regex/) {
  print "match found\n";
}