- From: Ian Hickson <ian@hixie.ch>
- Date: Sat, 21 Aug 2004 11:39:27 +0000 (UTC)
On Thu, 22 Jul 2004, Wrigley, Ave wrote: > > 1. What is the motivation behind the implicit ^ and $ (start and end of > string metacharacters)? I appreciate that in a lot of cases it makes it > easier for people to implicitly match the whole string, but (as is > mentioned in a sidebar) it make it potentially much more complex for > people who want to match substrings (especially where newlines are > possible). Would it be better just to comply with the ECMA-262 spec? I just added a note to the document that says: | The implicit ^ and $ characters are inserted because it is expected | that the overwhelming majority of use cases will be to require that | user input exactly match the given pattern. Authors who forget that | these characters are implied will immediately realise their mistake | during testing. Had the characters not been implied, requiring most | authors to insert them themselves, it is likely that authors who | forgot them would not catch their mistake as easily. > 2. Also (not wishing to compicate things too much!) did you consider > supporting regex modifiers (I guess case insensitivity would be > particularly useful)? I considered it but I couldn't really see an easy way to do it. If JS supported perl's scoped modifiers, that would work, but I don't think it does. > 3. Finally, is it necessary to have an ERROR_ for invalid regexes No, if the regexp is invalid, it is just ignored. > I guess the real point of 1 is consistency, and the expectation that the > input control will do what you expect. For example - I would expect that > if I already have a validator implemented in javascript, I should be > able to use the same regex pattern that I am using to validate an imput > field in the script. Most of the time you would, unless your pattern was specifically a substring search pattern, which seems unlikely. Thanks for your input! -- Ian Hickson U+1047E )\._.,--....,'``. fL http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
Received on Saturday, 21 August 2004 04:39:27 UTC