Accession Number : ADA312762

Title :   The Semantic Analyzer.

Corporate Author : AIR FORCE TEST BED WRIGHT-PATTERSON AFB OH

PDF Url : ADA312762

Report Date : 30 APR 1991

Pagination or Media Count : 20

Abstract : Once a document is marked up using an SGML-defined markup language, an SGML parser can validate the document against a specified Document Type Definition (DTD). This process ensures that the document's tags conform to the structure imposed by the DTD. An SGML parser is a powerful tool for one class of markup problems, namely SGML syntactical errors. However, in the markup of CALS documents, many errors are still made, and go unchallenged, for lack of a similar tool for detecting them. Within the confines of its structural check, an SGML parser is powerless to examine the semantics of a document -- in other words, the parser cannot assess the relevance of a given piece of text inside a particular element. Besides SGML-related markup rules, each DTD entails certain application-specific syntactic requirements -- in the case of CALS, requirements that go beyond those specified in the MIL-M-28001 DTD. For instance, no SGML requirements are violated when a CALS paragraph is left empty, but this condition is still syntactically wrong for a CALS application. This syntactic problem is a symptom of an underlying semantic problem -- an empty paragraph is meaningless. The Semantic Analyzer enables more powerful document analysis, combining the power of an SGML parser with the comprehensive pattern-matching capabilities of Exoterica's XGML Translator. A specification language is provided for the Semantic Analyzer, in order to allow development of customized analysis programs for specialized SGML applications.

Descriptors :   *VALIDATION, *SEMANTICS, *DOCUMENTS, *ANALYZERS, *PARSERS, REQUIREMENTS, SPECIFICATIONS, PROGRAMMING LANGUAGES, ERRORS, PATTERNS, LANGUAGE, SYNTAX, TRANSLATORS, LABELS.

Subject Categories : Linguistics
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE