"speed \\w+\"
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I don't see how that 'regexp' could capture 'speed'. It only will match successfully if the string contains the literal text "speed\w". That's because you've got a double-backslash in front of the 'w', so it's not functioning as a metacharacter, but rather as a literal character.

As for a regexp that will capture whatever comes after 'speed', how about...

m/speed(.+)/
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The regular expression could be made more specific as to what it captures if you define for us what part of the string following 'speed' constitutes "the value next to 'speed'".

You are right Dave.
I actually had the reg ex speed (\\w+) in my code, which captured the string 'speed'.
While typing in the Perl Monks I posted it as speed \\w+\" which was actually wrong.

The regexp...

m/speed (\\w+)/
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...won't capture 'speed'. I don't know where you keep coming up with that idea. If that's how your regular expression looked, it's a mistake. Here is why:

• Parenthesis mark matches that should be captured. The regexp you have shown is not trying to capture 'speed '. It's trying to capture '\\w+'.
• \\w+ is still a mistake. The metacharacter that directs the regular expression engine to capture a word-like character is '\w'. When you add the second backslash, as in '\\w' you are directing the regular expression parser to treat that subexpression as literal characters, not a special metacharacter. The first backslash essentially 'escapes' the second one. The result is that you are asking the RE engine to match the literal characters '\w', and also telling the RE engine (via the + quantifier) that there may be one or more 'w' characters. You must remove the double-backslash, leaving only one backslash as in speed (\w+). But that still won't capture 'speed', it will capture what comes after speed, if it's a word grouping.

Please read perlrequick and perlop. In perlop you'll want to read the gory details of quote and quote-like parsing. It may take awhile to sink in, but will help to understand the problem you're having with the double backslash.




Dave

You can use <code> and </code> tags around your data sample, and around the actual code that you have so far (not just the regex), and that will help others at the Monastery a lot.

Meanwhile, to capture the next full token of "non-whitespace" characters following the string "speed " in your example, try this:

    if ( /speed (\S+)/ ) {
        $token = $1;  # $token would be "basic-2.0"
        print "$token\n";
    }
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my ($everythingelse) = m/^speed (.+)/;
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That's not a regex, that's a string. And the \'s aren't making a lot of sense. And that string used as a regex wouldn't match anything in your string. So I'm not entirely sure what you're trying. A code sample would be appreciated.

  my $str = 'speed basic-2.0 basic-11.0';
  my ($one_basic) = $str =~ /speed\s*(\S+)/;
  my @all_basics = $str =~ /\s+(\S+)/g;
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Just guessing, though.

# This is the default, since we are not doing Unicode
use bytes;                

$_ = 'speed basic-2.0 5.5 basic-11.0';


# In order to match 'anything', we must also match any newlines
(my $result) = /\A \w+ \s+ (.*) \z/msxg;

print $result;
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($everything_after_speed = $string) =~ s/.*speed\s+//s;
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So, ramya2005, please, use strikethrus or some other method of updating; so those who come late to your posts can understand what you sought originally, and how you sought it.

Sorry for changing the original content of the post. Since my question was not clear to many people I updated to make ir more clear. Thanks for pointing out the issues. Now I added the original content and update