On 07-Jul-12 22:25, Andrei Alexandrescu wrote:
On 7/7/12 7:33 AM, Dmitry Olshansky wrote:
On 07-Jul-12 15:30, Roman D. Boiko wrote:
On Saturday, 7 July 2012 at 10:26:39 UTC, Roman D. Boiko wrote:
I think that Pegged can be heavily optimized in performance, and there
are no
fundamental issues which would make it inherently slower than LALR or
a hand-written D-specific parser.
Hmm... found an interesting article:
http://www.antlr.org/papers/LL-star-PLDI11.pdf
It describes some disadvantages of Packrat parsing, like problems with
debugging and error recovery. These are important for DCT, so I'll have
to perform additional research.
Yup, LL(*) is my favorite so far.
That's Terence Parr's discovery, right? I've always liked ANTLR, so if
PEGs turn out to have issues LL(*) sounds like a promising alternative.
How many semantics hacks does D's syntax need for a LL(*) parser?
I believe that it may need very few _semantic_ predicates. But there are
cases where infinite lookahead is a must. Can't recall which cases offhand.
Andrei
--
Dmitry Olshansky
