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If you still write parsers as recursive descent parser by hand, then this is because NOT ENOUGH MATH IS APPLIED IN PRACTICE (by programmers who think they don't
by auggierose 12y ago
If you still write parsers as recursive descent parser by hand, then this is because NOT ENOUGH MATH IS APPLIED IN PRACTICE (by programmers who think they don't need it).
- seanmcdirmid 12y agoNo, its because incremental performance and error recovery are more important than raw performance and expressiveness. If you think Dr. Odersky doesn't know enough math...not to mention most production compilers out there written by the best professionals in the field. Reality is a harsh mistress. My parsers, by the way, do things only your parsers could dream of: http://research.microsoft.com/en-us/people/smcdirm/liveprogramming.aspx?2 http://research.microsoft.com/en-us/people/smcdirm/liveprogr...
- loup-vaillant 12y ago> No, its because incremental performance and error recovery are more important than raw performance and expressiveness. As if the former would require less math than the latter… Really?
- seanmcdirmid 12y agoYep. Well, see my managed time paper; basically we use no fancy algorithmic tricks and it all works out fine. There are 2 ways to do incremental parsing: the hard way based on some fancy delta algorithm, and an easy way based on simple memoization and conservative recomputation. Academics especially often over think these problems when the simple solution often works fine, and performance wise you'd have to mess up pretty bad before parsing becomes a noticeable bottleneck.
- auggierose 12y agoWell, I am working on a new parsing algorithm as well. Using lots of math. Not sure if your dreams are bigger than mine.