Providing regex using an array

[dgrunwal]

Perl Monks, I am trying to use an array to list regex search choices. Code works if a single regex is inputted.

use strict;
use warnings;

sub main
{
    
      my @patterns = ("^abd", "ghi");
    my $file = 'C:\Perl64\bin\hello.txt';
    open(FH, $file) or die("File $file not found");
    
    while(my $String = <FH>)
    {
#         if($String = ~ /^abd /)
                if($String .= join ('/ && /', @patterns);
        {
            print "$String \n";
        }
    }
    close(FH);
}
main();

Error: Global symbol "@patterns" requires explicit package name at pattern2.pl line 7. Global symbol "@patterns" requires explicit package name at pattern2.pl line 14. syntax error at pattern2.pl line 14, near ");" Execution of pattern2.pl aborted due to compilation errors. What syntax error am I making? Best, David

[haukex]

You have unbalanced parens in your if, the semicolon on that line should be a closing paren.

If I understand correctly what your code is trying to do, you may be interested in my tutorial Building Regex Alternations Dynamically.

[LanX]

First of all please fix your indentation, you seem to be mixing spaces and tabs.

This might look ok in your editor, but your tab-length is 8 while we use 4 here.

It's hard to tell what you are trying to achieve, my best guess is to check that all regexes in an array individually match.

the following debugger-demo is using the fact that grep returns a count in scalar context

> perl -de0

  DB<134> @patterns = ("^abd", "ghi");

  DB<135> $string = "abd__ghi__"

  DB<136> p @patterns == grep { $string =~ $_ } @patterns
1
  DB<137>

  DB<137> $string = "abd__xhi__"

  DB<138> p @patterns == grep { $string =~ $_ } @patterns

  DB<139>

even easier if you use all from List::Util

  DB<139> use List::Util qw/all/

  DB<140> $string = "abd__ghi__"

  DB<141> p all { $string =~ $_ } @patterns
1
  DB<142>

[dgrunwal]

Thank you! Best, Dave