develooper Front page | perl.perl5.porters | Postings from March 2019

Re: RFC: Adding \p{foo=/re/}

Thread Previous | Thread Next
Karl Williamson
March 12, 2019 18:10
Re: RFC: Adding \p{foo=/re/}
Message ID:
On 2/5/19 3:47 PM, Karl Williamson wrote:
> The Unicode Technical Standard #18 on regular expressions suggests that 
> Unicode properties have what I'm calling a subpattern and they call 
> wildcard properties

This is now in blead by 1532347b696561120241d1e6221c028acedff019.
I meant to make this a merge commit, but forgot at the last minute.

> I am proposing to implement this in 5.30.  I already have a working 
> prototype, which you can find in
> and play with.  Attached is a script that exercises it to create a 
> pattern that matches IPV4 addresses in any language, and fails illegal 
> ones.  Thus the script would work for Bengali or Thai  numbers.  The 
> motivation for this came from Abigail.
> Certain things aren't clear to me about how it should behave.  Should 
> the default be anchored (as currently) so that you have to begin and/or 
> end with '.*' to unanchor it?  I think most uses will want it anchored 
> as implied by the equals sign, but that's not how other patterns behave, 
> and that inconsistency probably would be too confusing.  One thing that 
> might emphasize that it isn't anchored is to make them write
> \p{foo=~/bar/}
> (requiring a tilde)
> Comments?

Thread Previous | Thread Next Perl Programming lists via nntp and http.
Comments to Ask Bjørn Hansen at | Group listing | About