regex to deny characters?

arrow has asked for the wisdom of the Perl Monks concerning the following question:

I've been trying for a while now to simply (or not so simply) construct a regex to deny any characters others than lowercase letters, hyphens, and spaces. Simple, no? NO! I've tried every combination I could think of including making to match statments, one to try to match the lowercase letters, hypens, and spaces, and one to match all the characters I didn't want. Here are some of my desperate attempts:

/[a-z]+(?:[a-z\s-] *)/ (current)
/[a-z]+[-\s]*/
/[-\s(a-z)+]*/

but obviously none of them have worked. Any suggestions?

P.S. Thanks jwest for giving me the first one.

Just Another Perl Wannabe

Edit by tye, change title, close CENTER tag

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Re: so close, yet so far away... by gjb (Vicar) on Dec 06, 2002 at 21:29 UTC
Unless I get you completely wrong (which seems probable) wouldn't just `/^[a-z\- ]$/` do what you want? Note that this also matches the empty string, replace `+` by `` if you don't want that. Hope this helps, -gjb-	[reply] [d/l] [select]
Re: (nrd) so close, yet so far away... by newrisedesigns (Curate) on Dec 06, 2002 at 21:30 UTC
Why not: `/([a-z\-\s]+)/` Or am I missing something? John J Reiser newrisedesigns.com	[reply] [d/l]
Re: so close, yet so far away... by BrowserUk (Patriarch) on Dec 06, 2002 at 21:31 UTC
Try this. `for $w ('abd -def', 'Abcdef', 'abd_def', "abd\tdef") { print $w, $w =~ /^[-a-z\ ]+$/ ? 'ok' : 'not ok',$/ } abd -def ok Abcdef not ok abd_def not ok abd def not ok` [download] Use !~ to invert the match. Okay you lot, get your wings on the left, halos on the right. It's one size fits all, and "No!", you can't have a different color. Pick up your cloud down the end and "Yes" if you get allocated a grey one they *are* a bit damp under foot, but someone has to get them. Get used to the wings fast cos its an 8 hour day...unless the Govenor calls for a cyclone or hurricane, in which case 16 hour shifts are mandatory. Just be grateful that you arrived just as the tornado season finished. Them buggers are real work.	[reply] [d/l]
Re: so close, yet so far away... by dws (Chancellor) on Dec 06, 2002 at 21:32 UTC
I've been trying for a while now to simply (or not so simply) construct a regex to deny any characters others than lowercase letters, hyphens, and spaces. `if ( $string =~ /[^a-z- ]/ ) { ... }` will tell you if there are errant characters in $string.	[reply] [d/l]
Re: so close, yet so far away... by UnderMine (Friar) on Dec 06, 2002 at 21:28 UTC
Assuming that you wish to reject partial hyphenated words ie. 'this-' and '-that' `$string !~ /^(?:(?<!-)(?:[-a-z])(?<!-)\s)+$/` [download] I think... gets out the console Update forgot to ^$ it and invert it.. doh. Hope it helps UnderMine	[reply] [d/l]
Re: regex to deny characters? by arrow (Friar) on Dec 08, 2002 at 18:22 UTC
gjb and newrisedesigns, you did have me wrong. I needed at least one lower case letter and the ability to accept an optional hypen or space. In other words: `sdlfj OK` `dsfj-dlf OK` `dish dslf OK` `dsf-ldj sdf OK` `- NOT OK` `(space character) NOT OK` `*$)#&%_!@... NOT OK` Just Another Perl Wannabe	[reply] [d/l] [select]
(z) Re^2: regex to deny characters? by zigdon (Deacon) on Dec 09, 2002 at 14:44 UTC
OK, so you were pretty close: `while (<DATA>) { chomp; print "$_ "; if (/^[a-z][a-z \-]/) { print "OK\n"; } else { print "NOT OK\n"; } } __DATA__ sdlfj dsfj-dlf dish dslf dsf-ldj sdf - $)#&%_!@...` [download] -- Dan	[reply] [d/l]