tool: ssl

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Language:	S/SL (Syntax Semantic Language)
Version:	?
Parts:	parser bytecode compiler, runtime
Author:	Rick Holt, Jim Cordy <cordy@qucis.queensu.ca> (language), Rayan Zachariassen <rayan@cs.toronto.edu> (C implementation)
Location:	ftp://neat.cs.toronto.edu/pub/ssl.tar.Z
Description:	A better characterization is that S/SL is a language explicitly designed for making efficient recusive-descent parsers. Unlike most other languages, practicially the LEAST expensive thing you can do in S/SL is recur. A small language that defines input/output/error token names (& values), semantic operations (which are really escapes to a programming language but allow good abstration in the pseudo-code), and a pseudo-code program that defines a grammar by the token stream the program accepts. Alternation, control flow, and 1-symbol lookahead constructs are part of the language. What I call an S/SL "implementation", is a program that compiles this S/SL pseudo-code into a table (think byte-codes) that is interpreted by the S/SL table-walker (interpreter). I think the pseudo-code language is LR(1), and that the semantic mechanisms turn it into LR(N) relatively easily. + more powerful and cleaner than yac - slower than yacc
Reference:	Cordy, J.R. and Holt, R.C. [1980] Specification of S/SL: Syntax/Semantic Language, Computer Systems Research Institute, University of Toronto. "An Introduction to S/SL: Syntax/Semantic Language" by R.C. Holt, J.R. Cordy, and D.B. Wortman, in ACM Transactions on Programming Languages and Systems (TOPLAS), Vol 4, No. 2, April 1982, Pages 149-178.
Updated:	September 25th, 1989

category: compiler generators and related tools summary, or expanded.

category: text manipulation summary, or expanded.