Accession Number : AD0766295

Title :   Labelled Procedence Parsing,

Corporate Author : CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF COMPUTER SCIENCE

Personal Author(s) : Schkolnick,Mario

Report Date : JUL 1973

Pagination or Media Count : 19

Abstract : Precedence techniques have been widely used in the past in the construction of parsers. However, the restrictions imposed by them on the grammars were hard to meet. Thus, alteration of the rules of the grammar was necessary in order to make them acceptable to the parser. It was shown that, by keeping track of the possible set of rules that could be applied at any one time, one can enlarge the class of grammars considered. The possible set of rules to be considered is obtained directly from the information given by a labelled set of precedence relations. Thus, the parsers are easily obtained. Compared to the precedence parsers, this new method gives a considerable increase in the class of parsable grammars, as well as an improvement in error detection. An interesting consequence of this approach is a new decomposition technique for LR parsers. (Author)

Descriptors :   (*PROGRAMMING LANGUAGES, *GRAMMARS), MATHEMATICAL LOGIC, CONTEXT FREE GRAMMARS, ARTIFICIAL INTELLIGENCE, ALGORITHMS

Subject Categories : Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE