(41) The Syntactic Analyzer

	Machine:     PSI
	Environment: SIMPOS
	Language:    ESP
	Source Code: 1.5 MB
	Documents:   None

Overview

Sequential analyzer for syntax and semantics.

Configuration

SAX(Sequential Analyzer for syntaX and semantics) system is a syntactic and semantic analyzer based on logic programming. The grammar is written in DCG. SAX system provides with the user a facility to develop a grammar,and is composed of submodules, translator,and debugging tools. The configuration of SAX system is as follows.

Translator: Translator is translated grammar rules into a parsing program written in ESP.
Debugging utility: SAX system provides the grammar debugging utility,such as the grammar debugger,and graphic display utility.

Function

A characteristic of SAX system is as follows:

The SAX parsing algorithm is bottom-up parsing with top-down prediction. If there are some applicable grammar rules,all of them are executed at the same time. So we can analyze more effectively.
The SAX grammar rule is basically an extension of DCG(Definite Clause Grammar).
By using these extensions,we can analyze more effectively. The extension of DCG is as follows.

Delayed Extra Condition
In our system,a delayed extra condition can be specified. Basically,delayed extra conditions are used to compose semantic structure. The Prolog goals in the delayed extra conditions are evaluated after parsing.

Preference Calculation
The Preference rules enable us to calculate one of the plausible results using local information of the parsing process.

FTP

The Syntactic Analyzer [167K]

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