Showing papers by "Gordon V. Cormack published in 1989"
21 Jun 1989
TL;DR: This work presents metalanguage enhancements for context-free grammars that allow the syntax of programming languages to be completely described in a single grammar.
Abstract: The disadvantages of traditional two-phase parsing (a scanner phase preprocessing input for a parser phase) are discussed. We present metalanguage enhancements for context-free grammars that allow the syntax of programming languages to be completely described in a single grammar. The enhancements consist of two new grammar rules, the exclusion rule, and the adjacency-restriction rule. We also present parser construction techniques for building parsers from these enhanced grammars, that eliminate the need for a scanner phase.
89 citations
21 Jun 1989
TL;DR: Experience in constructing a substring parser for Pascal is described and a construction is given to produce an LR parser that recognizes any substring of the language generated by G.
Abstract: For a context-free grammar G, a construction is given to produce an LR parser that recognizes any substring of the language generated by G. The construction yields a conflict-free (deterministic) parser for the bounded context class of grammars (Floyd, 1964). The same construction yields either a left-to-right or right-to-left substring parser, as required to implement Non-correcting Syntax Error Recovery as proposed by Richter (1985). Experience in constructing a substring parser for Pascal is described.
25 citations
10 citations
01 Apr 1989
TL;DR: The motivation for a set of intertask communication primitives, the hardware support of these primitives), the architecture used in the Sylvan project which studies these issues, and the experience gained from various experiments conducted in this area are described.
Abstract: This paper describes the motivation for a set of intertask communication primitives, the hardware support of these primitives, the architecture used in the Sylvan project which studies these issues, and the experience gained from various experiments conducted in this area. We start by describing how these facilities have been implemented in a multiprocessor configuration that utilizes a shared backplane. This configuration represents a single node in the system. The latter part of the paper discusses a distributed multiple node system and the extension of the primitives that are used in this expanded environment.This research is funded by a strategic grant from the Natural Sciences and Engineering Research Council of Canada (Grant No. G1581).
7 citations