[ragel-users] Re: fexec bug in v5.15?

Carlos Antunes cmantu... at gmail.com
Thu Nov 9 04:28:51 UTC 2006

On 11/8/06, Adrian Thurston <thurs... at cs.queensu.ca> wrote:
> Carlos Antunes wrote:
> > On other hand, what is the cost of leaving the scanner and then
> > setting up and reentering the scanner? Maybe this could be the
> > behavior following an fexec or fhold? Not really knowing what I'm
> > talking about, my gut feeling is that this would be easy to implement,
> > no?
> I'm not sure what you mean. Could you elaborate?

Well, based on previous messages, you suggested that an fhold or fexec
immediately followed by an fret would be safe, correct? Now, let's say
I specify an fhold but not an fret. This case wouldn't be safe.
However, what if the scanner actually terminates and then reenters as
if starting anew? Because if an fhold followed by an fret is safe then
leaving the scanner altogether and then starting again should also be
safe, no?

> Just to let you know, sometime I'd like to implement trailing context, also
> known as follow patterns, which could be used to solve this problem.

Although I am too clueless to know exactly what you are talking about
(I'm not a computer science guy, just a lowly electrical engineer),
adding useful functionality for me sounds great! :-)



"We hold [...] that all men are created equal; that they are
endowed [...] with certain inalienable rights; that among
these are life, liberty, and the pursuit of happiness"
        -- Thomas Jefferson

More information about the ragel-users mailing list