henry@utzoo.uucp (Henry Spencer) (07/19/88)
In article <3863@rpp386.UUCP> jfh@rpp386.UUCP (The Beach Bum) writes: >the geneal case of trying to reduce the recursion present in the parser >would seem to require a potentially arbitrary amount of look ahead, or >as a minimum, the same amount of lookahead as the length of the shortest >sentence the parser is trying to recognize. clarifications, henry? The *general* case of reducing recursion is hard. However, if you're willing to do a little bit of lookahead, and punt to the full machinery when things get hard, you can get a lot of mileage out of avoiding the recursive plunge in things like "x = 2;". Many, many expressions consist of a single variable or constant; optimizing those cases may not be theoretically elegant but it's practically useful. > Pournelle signature quote >and what the hell does this mean??? Consider who the senior senator from Wisconsin is. -- Anyone who buys Wisconsin cheese is| Henry Spencer at U of Toronto Zoology a traitor to mankind. --Pournelle |uunet!mnetor!utzoo! henry @zoo.toronto.edu