WebOct 9, 2014 · A yyscan_t is a private structure used to hold your scanner state; yylval is where yylex () will put its token value when it’s called by yyparse (). You may be puzzled by the fact that the %lex-param declaration says ‘scanner’ but the scanner state argument ends up being ‘yyscanner’. That’s reasonable, I’m a bit puzzled by it myself. WebFlex allows you to store arbitrary, "extra" data in a scanner. This data is accessible through the accessor methods yyget_extra and yyset_extra from outside the scanner, and through the shortcut macro yyextra from within the scanner itself. They are defined as follows:

Compile error: unknown type name

http://www.flexscanmd.com/ edith levine

Lexical Analysis With Flex, for Flex 2.6.3: Extra Data

WebFlex, an automatic lexical analyser, is often used with Bison, to tokenise input data and provide Bison with tokens. [5] Bison was originally written by Robert Corbett in 1985.[1] Later, in 1989, Robert Corbett released another parser generator named Berkeley Yacc. Bison was made Yacc-compatible by Richard Stallman. [6] Web解析器以这种方式生成call flex例程： yychar = yylex (&yylval, scanner); 所以在bison输入中，我们必须包含scanner头文件 lex.yy.h 定义为： int yylex (YYSTYPE * yylval_param ,yyscan_t yyscanner); 但是 YYSTYPE 是在解析器头 parser.tab.h 中定义的，在我的例子中，我对bison说我的类型将是 double ： typedef double YYSTYPE; 现在是解决办法。 在 … WebReentrant Bison/Flex, как получить сообщение об ошибке для каждого экземпляра yyscan_t. Я пытаюсь создать программу, которая использует многопоточность с … edithley perilla