In my opinion, you should only be using a regular expression when the simpler solutions can't handle the problem. In this case, you can manage by just using split. Here's how:

#!/usr/bin/perl

use strict;
use warnings;

{
    my @names =
      ( [ 'John Doe Joe', 1 ], [ 'John D', 1 ], [ 'John ', 0 ],
        [ 'John', 0 ], );

    foreach my $lr (@names) {
        my ( $name, $success ) = @{$lr};
        my @result = split( /\s/, $name );

        if ( ( @result  > 1 &&  $success ) ||
             ( @result == 1 && !$success ) ) {

            print "$name split correctly, list has "
              . ( scalar @result )
              . " elements. - ";
        }
        else {

            print "$name split incorrectly, list has "
              . ( scalar @result )
              . " elements. - ";
        }
        print join('|',@result) . "\n";
    }
}

[download]

Rather than only using split after you've gone through a regexp, I'd just use split and look at the result you get. Running this gives me the following useful output:

$ perl -w 1130518.pl 
John Doe Joe split correctly, list has 3 elements. - John|Doe|Joe
John D split correctly, list has 2 elements. - John|D
John  split correctly, list has 1 elements. - John
John split correctly, list has 1 elements. - John
$

[download]

Alex / talexb / Toronto

Thanks PJ. We owe you so much. Groklaw -- RIP -- 2003 to 2013.

In reply to Re: Check for Spaces in a String by talexb
in thread Check for Spaces in a String by Anonymous Monk

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