Re: LR-regular parsers for dummies ?

: input and decides which action to take. The method works by
: constructing an RE for each of the conflicting actions, and then
: building a DFA that recognizes them simultanueously; whichever RE


Can anyone explain then what the intuitive idea is behind these two
algorithms ? (i.e. for constructing the RE -- done by a parser
generator I hope; and the operation of the DFA.) That exactly is the
densest part of the paper.


: Its not at all clear if its all that useful. In my experience, real
: grammars tend to be either LR(1) (in which case the extra power isn't
: needed) or ambiguous (in which case it doesn't help).


Real grammars may tend to be LR(1) as you say, but embedding actions
in a bison script may destroy the original LR(1)-ness (because a
reduce decision must be made sooner.) More powerful parser generators
might make life easier for the programmer and allow him/her to simply
copy the language specification into a parser generating script and
add embedded actions anywhere, without any need for tweaking.


Dirk van Deun Ceterum censeo Redmond delendum
--
Currently at: dirk@igwe.vub.ac.be http://student.vub.ac.be/~dvandeun
Permanent mail forwarder: dvandeun@poboxes.com

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