syntaxbuilder.syntax

来自「java 词法分析器,用于一般的C,C++,VB,PS/SQL 语句的翻译」· SYNTAX 代码 · 共 31 行

# SyntaxBuilder EBNF synax description, written in its own syntax
/* This is just an example, the real syntax is in SyntaxBuilderSemantic.java */

// START rule
syntax	::=	rule +	// a syntax consists of one or more rules
	;

set	::=	`bnf_chardef` ".." `bnf_chardef`	// character set definition
	;

intersectionstartunit	::=	set | `identifier` | `ruleref`	// intersection of character sets
	;
intersectionunit	::=	`bnf_chardef` | `stringdef` | intersectionstartunit
	;
intersection	::=	intersectionstartunit ('-' intersectionunit)+
	;

sequnit	::=	intersection | intersectionunit | '(' unionseq ')' 	// unit of a sequence
	;
quantifiedsequnit	::=	sequnit `quantifier` | sequnit	// unit can be quantified
	;
sequence	::=	quantifiedsequnit *	// sequence of units with significant order
	;

unionseq	::=	sequence ('|' sequence)*	// rule alternatives
	;
rule	::=	`identifier` "::=" unionseq ';'	// syntax rule
	;

ignored ::= `comment` | `whitespaces`
	;