JFlex Lexer.多行字符串

Question

我正在尝试使用JFlex解​​析一些使用多行字符串文字的语言.

例子:

'''
this is a valid multiline string literal with 'quoted' word
'''

我创造了两种状态:

%x IN_QUOTED_STRING
%x IN_MULTILINE_QUOTED_STRING

并创建了几个宏和规则:

QUOTED_STRING_TAIL=[^\']* "'"
QUOTED_STRING_START="@"? "'"
MULTILINE_QUOTED_STRING_START = "@"? "'''"
MULTILINE_QUOTED_STRING_TAIL = [.]* "'''"

%%

<YYINITIAL> {MULTILINE_QUOTED_STRING_START} {yybegin(IN_MULTILINE_QUOTED_STRING);}
<YYINITIAL> {QUOTED_STRING_START} {yybegin(IN_QUOTED_STRING);}

<IN_QUOTED_STRING> {QUOTED_STRING_TAIL} {yybegin(YYINITIAL); return STRING;}
<IN_MULTILINE_QUOTED_STRING> {MULTILINE_QUOTED_STRING_TAIL} {yybegin(YYINITIAL); return STRING;}

但它不起作用.我得到"错误:无法匹配输入"

任何人都可以帮助我解决问题吗？

Answer 1

OP 写道：

对我有用：

QUOTED_LITERAL="'" ([^\\\'\r\n] | {ESCAPE_SEQUENCE} | (\[\r\n]))* ("'"|\)?
ESCAPE_SEQUENCE=\[^\r\n] 
ANY_ESCAPE_SEQUENCE = \[^] 
THREE_QUO = (\"\"\") 
ONE_TWO_QUO = (\"[^\"]) | (\"\[^]) | (\"\"[^\"]) | (\"\"\[^]) 
QUO_STRING_CHAR = [^\\\"] | {ANY_ESCAPE_SEQUENCE} | {ONE_TWO_QUO}
TRIPLE_QUOTED_LITERAL = {THREE_QUO} {QUO_STRING_CHAR}* {THREE_QUO}?
%%
<YYINITIAL> {TRIPLE_QUOTED_LITERAL }{ return STRING; } 
<YYINITIAL> {QUOTED_LITERAL} { return STRING; }