Java Antlr4语法编译错误
我为ANTLR4制作了自己的国际象棋PGN语法,但我得到了一个java stacktrace错误: Pgn.g4语法:Java Antlr4语法编译错误,java,antlr4,chess,Java,Antlr4,Chess,我为ANTLR4制作了自己的国际象棋PGN语法,但我得到了一个java stacktrace错误: Pgn.g4语法: grammar Pgn; file: game (NEWLINE+ game)*; game: (tag+ NEWLINE+)? notation; tag: '['TAG_TYPE "TAG_VALUE"']'; notation: move+ END_RESULT?; move: MOVE_NUMBER\. MOVE_DESC
grammar Pgn;
file: game (NEWLINE+ game)*;
game: (tag+ NEWLINE+)? notation;
tag: '['TAG_TYPE "TAG_VALUE"']';
notation: move+ END_RESULT?;
move: MOVE_NUMBER\. MOVE_DESC MOVE_DESC #CompleteMove
| MOVE_NUMBER\. MOVE_DESC #OnlyWhiteMove
| MOVE_NUMBER\.\.\. MOVE_DESC #OnlyBlackMove
;
END_RESULT: '1-0'
| '0-1'
| '1/2-1/2'
;
TAG_TYPE: LETTER+;
TAG_VALUE: .*;
MOVE_NUMBER: DIGIT+;
MOVE_DESC: .*;
NEWLINE: \r? \n;
SPACES: [ \t]+ -> skip;
fragment LETTER: [a-zA-Z];
fragment DIGIT: [0-9];
这是错误输出:
$ antlr4 Pgn.g4
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:11 required (...)+ loop did not match anything at input 'r'
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:15 mismatched tree node: n expecting <UP>
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:11 required (...)+ loop did not match anything at input 'r'
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:15 mismatched tree node: n expecting <UP>
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:11 required (...)+ loop did not match anything at input 'r'
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:15 mismatched tree node: n expecting <UP>
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:11 required (...)+ loop did not match anything at input 'r'
org\antlr\v4\parse\GrammarTreeVisitor.g: node from line 24:15 mismatched tree node: n expecting <UP>
error(20): internal error: Rule LETTER undefined
error(20): internal error: element list has first|last == null
Exception in thread "main" java.lang.NullPointerException
at org.antlr.v4.automata.ParserATNFactory.elemList(ParserATNFactory.java:445)
at org.antlr.v4.automata.ParserATNFactory.alt(ParserATNFactory.java:414)
at org.antlr.v4.parse.ATNBuilder.alternative(ATNBuilder.java:567)
at org.antlr.v4.parse.ATNBuilder.block(ATNBuilder.java:400)
at org.antlr.v4.parse.ATNBuilder.subrule(ATNBuilder.java:1185)
at org.antlr.v4.parse.ATNBuilder.element(ATNBuilder.java:887)
at org.antlr.v4.parse.ATNBuilder.alternative(ATNBuilder.java:550)
at org.antlr.v4.parse.ATNBuilder.ruleBlock(ATNBuilder.java:289)
at org.antlr.v4.automata.ParserATNFactory._createATN(ParserATNFactory.java:148)
at org.antlr.v4.automata.LexerATNFactory.createATN(LexerATNFactory.java:94)
at org.antlr.v4.Tool.processNonCombinedGrammar(Tool.java:407)
at org.antlr.v4.Tool.process(Tool.java:376)
at org.antlr.v4.Tool.processGrammarsOnCommandLine(Tool.java:343)
at org.antlr.v4.Tool.main(Tool.java:190)
$antlr4 Pgn.g4
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:11行中的节点必需(…)+循环与输入“r”处的任何内容都不匹配
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:15行中的节点不匹配树节点:n
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:11行中的节点必需(…)+循环与输入“r”处的任何内容都不匹配
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:15行中的节点不匹配树节点:n
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:11行中的节点必需(…)+循环与输入“r”处的任何内容都不匹配
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:15行中的节点不匹配树节点:n
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:11行中的节点必需(…)+循环与输入“r”处的任何内容都不匹配
org\antlr\v4\parse\GrammarTreeVisitor.g:第24:15行中的节点不匹配树节点:n
错误(20):内部错误:规则字母未定义
错误(20):内部错误:元素列表的first | last==null
线程“main”java.lang.NullPointerException中出现异常
位于org.antlr.v4.automata.ParserATNFactory.elemList(ParserATNFactory.java:445)
位于org.antlr.v4.automata.ParserATNFactory.alt(ParserATNFactory.java:414)
位于org.antlr.v4.parse.ATNBuilder.alternative(ATNBuilder.java:567)
位于org.antlr.v4.parse.ATNBuilder.block(ATNBuilder.java:400)
位于org.antlr.v4.parse.ATNBuilder.subrule(ATNBuilder.java:1185)
位于org.antlr.v4.parse.ATNBuilder.element(ATNBuilder.java:887)
位于org.antlr.v4.parse.ATNBuilder.alternative(ATNBuilder.java:550)
位于org.antlr.v4.parse.ATNBuilder.ruleBlock(ATNBuilder.java:289)
位于org.antlr.v4.automata.ParserATNFactory.\u createATN(ParserATNFactory.java:148)
位于org.antlr.v4.automata.lexeranfactory.createATN(lexeranfactory.java:94)
位于org.antlr.v4.Tool.processNonCombinedGrammar(Tool.java:407)
位于org.antlr.v4.Tool.process(Tool.java:376)
位于org.antlr.v4.Tool.processGrammarsOnCommandLine(Tool.java:343)
位于org.antlr.v4.Tool.main(Tool.java:190)
那么,我的语法有什么问题
(请注意,这篇文章可能比我在文章中披露的更进一步,因为我在文章中出现了语法错误)。有两件事出了问题:
为什么
标记值
周围有双引号?如果要匹配标记TAG\u值
:TAG:'['TAG\u TYPE TAG\u值'],请删除引号代码>
如果要匹配文字
(点),需要在其周围加引号(而不是转义!):移动\u编号。“”移动\u描述移动\u描述
同样,如果要匹配文本,请在其周围加引号:NEWLINE:'\r'?'\n′代码>
这些规则将吞噬整个输入流。与现在相比,您需要另一种方法来匹配标记值和移动描述。不要使用*
编辑
这里有一个现有的PGN语法:非常感谢。对于“TAG_值”,我希望捕获双引号中的一些内容,而不将它们提取到我的TAG_值lexer中。现在,另一个要点是避免使用两个wilcard(.*):因为我想匹配任何可打印字符,包括空格。我找到了可打印字符的[:print:]:现在需要一种方法来避免标记值周围的双引号。。。又一次没有抓住他们。
tag: '['TAG_TYPE "TAG_VALUE"']';
MOVE_NUMBER\. MOVE_DESC MOVE_DESC
NEWLINE: \r? \n;
TAG_VALUE: .*;
...
MOVE_DESC: .*;