我发现柠檬here的Lua 5.1语法（页面末尾的清单1）：
%fallback OPEN '(' .
chunk ::= block .
semi ::= ';' .
semi ::= .
block ::= scope statlist .
block ::= scope statlist laststat semi .
ublock ::= block 'until' exp .
scope ::= .
scope ::= scope statlist binding semi.
statlist ::= .
statlist ::= statlist stat semi .
stat ::= 'do' block 'end' .
stat ::= 'while' exp 'do' block 'end' .
stat ::= repetition 'do' block 'end' .
stat ::= 'repeat' ublock .
stat ::= 'if' conds 'end' .
stat ::= 'function' funcname funcbody .
stat ::= setlist '=' explist1 .
stat ::= functioncall .
repetition ::= 'for' NAME '=' explist23 .
repetition ::= 'for' namelist 'in' explist1 .
conds ::= condlist .
conds ::= condlist 'else' block .
condlist ::= cond .
condlist ::= condlist 'elseif' cond .
cond ::= exp 'then' block .
laststat ::= 'break' .
laststat ::= 'return' .
laststat ::= 'return' explist1 .
binding ::= 'local' namelist .
binding ::= 'local' namelist '=' explist1 .
binding ::= 'local' 'function' NAME funcbody .
funcname ::= dottedname .
funcname ::= dottedname ':' NAME .
dottedname ::= NAME .
dottedname ::= dottedname '.' NAME .
namelist ::= NAME .
namelist ::= namelist ',' NAME .
explist1 ::= exp .
explist1 ::= explist1 ',' exp .
explist23 ::= exp ',' exp .
explist23 ::= exp ',' exp ',' exp .
%left 'or' .
%left 'and' .
%left '<' '<=' '>' '>=' '==' '~=' .
%right '..' .
%left '+' '-' .
%left '*' '/' '%' .
%right 'not' '#' .
%right '^' .
exp ::= 'nil'|'true'|'false'|NUMBER|STRING|'...' .
exp ::= function .
exp ::= prefixexp .
exp ::= tableconstructor .
exp ::= 'not'|'#'|'-' exp . ['not']
exp ::= exp 'or' exp .
exp ::= exp 'and' exp .
exp ::= exp '<'|'<='|'>'|'>='|'=='|'~=' exp .
exp ::= exp '..' exp .
exp ::= exp '+'|'-' exp .
exp ::= exp '*'|'/'|'%' exp .
exp ::= exp '^' exp .
setlist ::= var .
setlist ::= setlist ',' var .
var ::= NAME .
var ::= prefixexp '[' exp ']' .
var ::= prefixexp '.' NAME .
prefixexp ::= var .
prefixexp ::= functioncall .
prefixexp ::= OPEN exp ')' .
functioncall ::= prefixexp args .
functioncall ::= prefixexp ':' NAME args .
args ::= '(' ')' .
args ::= '(' explist1 ')' .
args ::= tableconstructor .
args ::= STRING .
function ::= 'function' funcbody .
funcbody ::= params block 'end' .
params ::= '(' parlist ')' .
parlist ::= .
parlist ::= namelist .
parlist ::= '...' .
parlist ::= namelist ',' '...' .
tableconstructor ::= '{' '}' .
tableconstructor ::= '{' fieldlist '}' .
tableconstructor ::= '{' fieldlist ','|';' '}' .
fieldlist ::= field .
fieldlist ::= fieldlist ','|';' field .
field ::= exp .
field ::= NAME '=' exp .
field ::= '[' exp ']' '=' exp .
我尝试使用
lemon -c lua51.y进行编译，但出现很多错误：lua51.y:3: %fallback argument "'" should be a token
lua51.y:3: %fallback argument "(" should be a token
lua51.y:3: %fallback argument "'" should be a token
lua51.y:7: Illegal character on RHS of rule: "'".
lua51.y:12: Illegal character on RHS of rule: "'".
lua51.y:20: Illegal character on RHS of rule: "'".
lua51.y:21: Illegal character on RHS of rule: "'".
lua51.y:22: Illegal character on RHS of rule: "'".
lua51.y:23: Illegal character on RHS of rule: "'".
lua51.y:24: Illegal character on RHS of rule: "'".
lua51.y:25: Illegal character on RHS of rule: "'".
lua51.y:26: Illegal character on RHS of rule: "'".
lua51.y:29: Illegal character on RHS of rule: "'".
lua51.y:30: Illegal character on RHS of rule: "'".
lua51.y:33: Illegal character on RHS of rule: "'".
lua51.y:35: Illegal character on RHS of rule: "'".
lua51.y:36: Illegal character on RHS of rule: "'".
lua51.y:38: Illegal character on RHS of rule: "'".
lua51.y:39: Illegal character on RHS of rule: "'".
lua51.y:40: Illegal character on RHS of rule: "'".
lua51.y:42: Illegal character on RHS of rule: "'".
lua51.y:43: Illegal character on RHS of rule: "'".
lua51.y:44: Illegal character on RHS of rule: "'".
lua51.y:47: Illegal character on RHS of rule: "'".
lua51.y:50: Illegal character on RHS of rule: "'".
lua51.y:50: Token "'" should be either "%" or a nonterminal name.
lua51.y:50: Token "NAME" should be either "%" or a nonterminal name.
lua51.y:50: Token "." should be either "%" or a nonterminal name.
lua51.y:53: Illegal character on RHS of rule: "'".
lua51.y:56: Illegal character on RHS of rule: "'".
lua51.y:57: Illegal character on RHS of rule: "'".
lua51.y:58: Illegal character on RHS of rule: "'".
lua51.y:60: Can't assign a precedence to "'".
lua51.y:60: Can't assign a precedence to "or".
lua51.y:60: Can't assign a precedence to "'".
lua51.y:61: Can't assign a precedence to "'".
lua51.y:61: Can't assign a precedence to "and".
lua51.y:61: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "<".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "<".
lua51.y:62: Can't assign a precedence to "=".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to ">".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to ">".
lua51.y:62: Can't assign a precedence to "=".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "=".
lua51.y:62: Can't assign a precedence to "=".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:62: Can't assign a precedence to "~".
lua51.y:62: Can't assign a precedence to "=".
lua51.y:62: Can't assign a precedence to "'".
lua51.y:63: Can't assign a precedence to "'".
lua51.y:63: Token "." should be either "%" or a nonterminal name.
lua51.y:63: Token "'" should be either "%" or a nonterminal name.
lua51.y:63: Token "." should be either "%" or a nonterminal name.
lua51.y:64: Can't assign a precedence to "'".
lua51.y:64: Can't assign a precedence to "+".
lua51.y:64: Can't assign a precedence to "'".
lua51.y:64: Can't assign a precedence to "'".
lua51.y:64: Can't assign a precedence to "-".
lua51.y:64: Can't assign a precedence to "'".
lua51.y:65: Can't assign a precedence to "'".
lua51.y:65: Can't assign a precedence to "*".
lua51.y:65: Can't assign a precedence to "'".
lua51.y:65: Can't assign a precedence to "'".
lua51.y:65: Can't assign a precedence to "/".
lua51.y:65: Can't assign a precedence to "'".
lua51.y:65: Can't assign a precedence to "'".
lua51.y:65: Can't assign a precedence to "%".
lua51.y:65: Can't assign a precedence to "'".
lua51.y:66: Can't assign a precedence to "'".
lua51.y:66: Can't assign a precedence to "not".
lua51.y:66: Can't assign a precedence to "'".
lua51.y:66: Can't assign a precedence to "'".
lua51.y:66: Can't assign a precedence to "#".
lua51.y:66: Can't assign a precedence to "'".
lua51.y:67: Can't assign a precedence to "'".
lua51.y:67: Can't assign a precedence to "^".
lua51.y:67: Can't assign a precedence to "'".
lua51.y:69: Illegal character on RHS of rule: "'".
lua51.y:69: Token "." should be either "%" or a nonterminal name.
lua51.y:69: Token "." should be either "%" or a nonterminal name.
lua51.y:69: Token "'" should be either "%" or a nonterminal name.
lua51.y:69: Token "." should be either "%" or a nonterminal name.
lua51.y:73: Illegal character on RHS of rule: "'".
lua51.y:73: The precedence symbol must be a terminal.
lua51.y:73: Missing "]" on precedence mark.
lua51.y:73: Token "'" should be either "%" or a nonterminal name.
lua51.y:73: Token "]" should be either "%" or a nonterminal name.
lua51.y:74: Illegal character on RHS of rule: "'".
lua51.y:75: Illegal character on RHS of rule: "'".
lua51.y:76: Illegal character on RHS of rule: "'".
lua51.y:77: Illegal character on RHS of rule: "'".
lua51.y:77: Token "." should be either "%" or a nonterminal name.
lua51.y:77: Token "'" should be either "%" or a nonterminal name.
lua51.y:77: Expected to see a ":" following the LHS symbol "exp".
lua51.y:79: Illegal character on RHS of rule: "'".
lua51.y:79: Illegal declaration keyword: "'".
lua51.y:80: Illegal character on RHS of rule: "'".
lua51.y:83: Illegal character on RHS of rule: "'".
lua51.y:86: Illegal character on RHS of rule: "'".
lua51.y:87: Illegal character on RHS of rule: "'".
lua51.y:87: Token "'" should be either "%" or a nonterminal name.
lua51.y:87: Token "NAME" should be either "%" or a nonterminal name.
lua51.y:87: Token "." should be either "%" or a nonterminal name.
lua51.y:91: Illegal character on RHS of rule: "'".
lua51.y:94: Illegal character on RHS of rule: "'".
lua51.y:96: Illegal character on RHS of rule: "'".
lua51.y:97: Illegal character on RHS of rule: "'".
lua51.y:101: Illegal character on RHS of rule: "'".
lua51.y:103: Illegal character on RHS of rule: "'".
lua51.y:105: Illegal character on RHS of rule: "'".
lua51.y:109: Illegal character on RHS of rule: "'".
lua51.y:109: Token "." should be either "%" or a nonterminal name.
lua51.y:109: Token "." should be either "%" or a nonterminal name.
lua51.y:109: Token "'" should be either "%" or a nonterminal name.
lua51.y:109: Token "." should be either "%" or a nonterminal name.
lua51.y:110: Illegal character on RHS of rule: "'".
lua51.y:110: Token "." should be either "%" or a nonterminal name.
lua51.y:110: Token "." should be either "%" or a nonterminal name.
lua51.y:110: Token "'" should be either "%" or a nonterminal name.
lua51.y:110: Token "." should be either "%" or a nonterminal name.
lua51.y:112: Illegal character on RHS of rule: "'".
lua51.y:113: Illegal character on RHS of rule: "'".
lua51.y:114: Illegal character on RHS of rule: "'".
lua51.y:117: Illegal character on RHS of rule: "'".
lua51.y:120: Illegal character on RHS of rule: "'".
lua51.y:121: Illegal character on RHS of rule: "'".
少了什么东西？
最佳答案
看起来就像几年前的工作。它用于我创建但不再维护的柠檬的修改版本，该版本在Lua中生成了解析器。
为了将它与开箱即用的柠檬解析器一起使用，您将必须用命名标记替换所有引用文字的实例。请参见lemon documentation中有关终端和非终端的部分。 （您链接的页面中有关于此的注释。）
与yacc / bison不同，柠檬不需要您声明令牌名称，因为此类名称必须以大写字母开头。像yacc / bison一样，Lemon将生成一个带有这些名称定义的头文件，您可以在扫描程序的实现中#include。 （使用flex生成用于柠檬分析器的扫描器很容易，但是您应该仔细阅读柠檬文档；柠檬分析器由扫描器调用，而不是调用扫描器。）
yacc / bison中没有几个柠檬功能，这会使将语法转换为yacc / bison变得复杂：
柠檬中的|标记未记录，与yacc / bison中的|用法不同；它只能用于创建备用终端令牌的列表。在yacc / bison中，您可以创建这种形式的非终结符，但是非终结符不参与优先级规则。在柠檬中，替代列表是“多终端”，不会干扰优先规则。因此，在yacc / bison中，您将不得不为每个备用终端使用令牌备用来复制产品。另一种yacc / bison方法是对组中的所有备选方案使用单个词汇标记，通过其语义值（可以为enum）对其进行区分。这对于操作员终端将很好地工作，但是对于像','|';'这样的替代项将不起作用，因为这些替代项在整个语法中不一致。
没有%fallback的yacc /野牛等效物，也没有简单的解决方法。