Re: Set::Scalar - Regexp as method parameter?

Does this already work [...] ?

Taking a peek at the source, apparently not, so you'd need to augment has with your own functionality, either be redefining it directly or via a subclass.

[...] and I'm doing something wrong to achieve my goal ?

Trying to pass a bare regex isn't going to work, as you'll end up passing it's return value against (in your example anyway) whatever $_ is before you even get to the sub.

Instead, you should use qr (my personal preference) or pass the string you want to use (ie, the regex minus the enclosing //'s) so that the regex gets evaluated when you really want it to: inside the function/method...

foo( qr/ba[rz]|quux/ );
foo(   'ba[rz]|quux' );

sub foo {
    my $regex = shift;

      # //'s not necessary if $regex 
      # was built with qr.
    return grep /$regex/ => @foo;
}
[download]

[...] How to alternatively implement that?

Depending on your needs, you might be able to use Quantum::Superpositions' any function...

any(@set) =~ /c$(.+)$/;

... although I note I couldn't get it working with Q::S's all, so be sure to test for yourself.

--k.

Comment on Re: Set::Scalar - Regexp as method parameter? Select or Download Code

Replies are listed 'Best First'.
Re: Re: Set::Scalar - Regexp as method parameter? by Juerd (Abbot) on Apr 27, 2002 at 20:57 UTC
//'s not necessary if $regex was built with qr. Actually, if you leave out the slashes, the regex is put in string context, and the speed gain is lost. `$foo =~ '^string literal$'; # Does not equal /\Q^string literal$/ $foo =~ $string; $foo =~ subroutine(); $foo =~ bareword; # Unless $INC{'strict.pm'} $foo =~ $precompiled_regex; # Is stringified first! $foo =~ /$precompiled_regex/; # Faster` [download] I've even seen people do bizarre things because they think `qr//`s are faster without slashes: `# Bad: (well, it works, but not the way you want it to) $foo =~ $qr; $foo =~ s//bar/; # Good: $foo =~ s/$qr/bar/;` [download] - Yes, I reinvent wheels. - Spam: Visit eurotraQ.	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re: Re: Set::Scalar - Regexp as method parameter?
by Juerd (Abbot) on Apr 27, 2002 at 20:57 UTC

//'s not necessary if $regex was built with qr.

Actually, if you leave out the slashes, the regex is put in string context, and the speed gain is lost.

$foo =~ '^string literal$';   # Does not equal /\Q^string literal$/
$foo =~ $string;
$foo =~ subroutine();
$foo =~ bareword;             # Unless $INC{'strict.pm'}
$foo =~ $precompiled_regex;   # Is stringified first!

$foo =~ /$precompiled_regex/; # Faster
[download]

qr//

# Bad: (well, it works, but not the way you want it to)
$foo =~ $qr;
$foo =~ s//bar/;

# Good:
$foo =~ s/$qr/bar/;
[download]

- Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

[reply]
[d/l]
[select]