Accession Number:

ADA056839

Title:

An LALR(1) Parser Grammar for FORTRAN.

Descriptive Note:

Interim technical rept.,

Corporate Author:

COLORADO UNIV BOULDER DEPT OF COMPUTER SCIENCE

Personal Author(s):

• Rauhauser,Russ C.

Report Date:

1978-06-01

Pagination or Media Count:

63.0

Abstract:

An automatic parser generator is a tool for quickly implementing programming language parsers. Parser generators based upon LR parsing have been built for grammars satisfying the LRo, SLR1, and LALR1 properties. Speed of the resulting parser is comparable to that of a hand coded recursive descent parser. DAVE, an automatic program testing aid, requires a flexible, easy-to-implement parser. This report presents an LALR1 grammar for ANSI standard FORTRAN, suitable as input to an automatic parser generator. Its use in building DAVE provides a measure of the desired flexibility, since new parsers for FORTRAN dialects may be produced by simply modifying the existing grammar. A powerful meta-language is used to describe the grammar. Its features are summarized, including the method for specifying automatic construction of intermediate-text structure trees during parsing. The report concludes with a discussion of some of the more important decisions made during development of the grammar. Author

Descriptors:

• *FORTRAN
• *COMPUTER PROGRAM VERIFICATION
• *PARSERS
• *GRAMMARS
• COMPUTER PROGRAMS
• PROGRAMMING LANGUAGES
• SYNTAX
• CONTEXT FREE GRAMMARS
• TRANSFORMATIONAL GRAMMARS

Subject Categories:

• Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE