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Ico Doornekamp wrote:
* On 2010-11-18 Wesley Smith <> wrote  :

I too found LPEG mysterious at first.  It took a lot of playing around
with it before it really made sense.  The thing that confused me the
most was the V grammar rule function, but in the end I was over
thinking it.  For someone who is not familiar with PEG and string
matching, the terminology looks really obscure.  What I would suggest
is trying some really simple patterns without going in to grammars
until you feel more comfortable with LPEG.  Try something dead simple
like matching patterns with 1 character, then 2 characters, then
generating a search in a larger string for those patterns.  I think
this will help give you a taste of what LPEG is all about.

For what it's worth, my two cents. I totaly agree with this: It is very
possible to 'grow' a grammar by incrementally adding small pieces and
learning on the fly, testing the results every run to see what exactly
is going on. I had some troubles understanding a lot of  details of the
LPEG grammar at first as well, but I was able to build a complete SIP
parser in a two or three days from the ground up, with no previous LPEG
experience at all.

Wes & Ico:
Thank you very much for the prompt response and for a bit of hope and encouragement :-)
I'll follow your advices and try harder.
I'd really pity myself for not being able to use such a useful tool (I've been reading about its power since my early lurker days on this list ~ 2 yrs ago!)

Best Regards,

-- Lorenzo