Le 2015-04-22 08:44, [email protected] a écrit :
Well, I wrote a little grammar (see attachment), but I don't see any
way to pass the pattern as an argument to the grammar, is it possible?
You cannot as REGULAR-GRAMMARs are compiled. If you need to compute new
grammars at runtime, you will have to use eval :-(. For instance, you
can use something such as:
(define (mk-regular-grammar pattern)
(eval `(regular-grammar () (,pattern "blabla"))))
Although not recommended in general, this solution will deliver decent
performance in your case.
As the system we try to emulate is a Python library, the performance
should be comparable.
The other solution would be to use pregexp (your first intuition) but
as pregexp requires a string, you will have to read the whole file in
memory first, which means that this solution will only work for toy
examples.
As a side note, if your pattern is basic regular expression only made
of sequences of characters, then you might prefer using KPM and mmap.
KMP, I suppose? We need Regexps more complex than just strings. But I am
curious about the way Perl manages multi-lines queries, we would do the
same.
Cheers.
--
Laurent Bloch - http://www.laurentbloch.org/ - [email protected]
