Perl regex to match metacharacters

Question

I have a text file which is like following.

Jack       Boy
Jill       Girl
Jam        ????
John       Boy
Michelle   Girl

I have written this, which I intended to match only lines that contain two words and not the line Jam ???? . It is not working.

if ( $line =~ ( /(\w+)\s+(\w+)/ ) && !( m/\?\?\?\?/ ) ) 

Answer 1

If you are also processing the data then a regular expression is the wrong tool for this.

You should simply split each line into fields and check whether the second field contains nothing but question marks.

Like this

use strict;
use warnings;

while (my $line = <DATA>) {
  my @fields = split ' ', $line;
  next unless $fields[1] =~ /[^?]/;
  print $line;
}

__DATA__
Jack       Boy
Jill       Girl
Jam        ????
John       Boy
Michelle   Girl

output

Jack       Boy
Jill       Girl
John       Boy
Michelle   Girl

Answer 2

Are these the only two options: two words or a word and ???? ?

If so, the first part /(\\w)+\\s+(\\w+)/ is enough.

\\w doesn't match ? .

Answer 3

I see no need to match metacharacters for your specific input:

use warnings;
use strict;

while (<DATA>) {
    print if /(\w+)\s+(\w+)/;
}

__DATA__
Jack       Boy
Jill       Girl
Jam        ????
John       Boy
Michelle   Girl

Answer 4

Previous answers have covered that this isn't really the right process, but sometimes filtering strings by regular expression is helpful in a single if statement.

You almost had it! It's missing the matching operator in the second half of the if statement.

if ($line =~ (/(\\w+)\\s+(\\w+)/) && !($line =~ m/\\?\\?\\?\\?/))