Re: [Emacs-diffs] master 938d252 4/4: Make regex matching reentrant; update syntax during match

[Perry E. Metzger]

On Tue, 19 Jun 2018 10:30:02 -0400 "Perry E. Metzger"
<address@hidden> wrote:
> > > Oh, and re2 isn't built for POSIX compliance. It has no
> > > constructs that require backtracking etc.    
> > 
> > No DFA engine can do backtracking.  
> 
> Correct, but there are regexp libraries that will switch between DFA
> and non-DFA implementations depending on whether the regexp has
> constructs in it that require backtracking.

Just to be explicit: TRE does this, IIRC. It certainly implements
backreferences, which re2 does not. (And, it has provisions in its
API for handling things like gap buffers. The main problem is it is
unmaintained.)

Perry
-- 
Perry E. Metzger                address@hidden