Bison:将联合语义类型与C++解析器一起使用

我一直在尝试在Bison中设置一个小解析器，但是当我尝试构建它时，我得到：

stone.tab.cc：在成员函数'virtual int yy：：StoneParser：:p arse()'中： stone.tab.cc：507：81：错误：从类型为"yy：：StoneParser：：semantic_type*"的右值初始化类型为"StoneDriver&"的非常量引用无效 yyla.type = yytranslate_ (yylex (&yyla.value， &yyla.location， driver));

我怀疑原因是将联合定义的语义类型与野牛生成的C++编译器一起使用时存在问题，但我似乎无法解决它......

如何生成具有"联合"语义定义的有效C++野牛解析器？

石.yy：

%skeleton "lalr1.cc"
%require "3.0.4"
%defines
%define parser_class_name {StoneParser}
%code requires
{
# include <string>
class StoneDriver;
}
%param { StoneDriver& driver }
%locations
%code
{
# include "StoneDriver.hpp"
}
%union
{
int intVal;
char* stringVal;
}
%token <stringVal> KEY_ENUM
%token <stringVal> KEY_CLASS
%token K_TEST
%token T_ID
%type <stringVal> class
%type <stringVal> enum
%%
input: toplevel_declarations
toplevel_declarations: toplevel_declarations toplevel_declaration
| %empty
toplevel_declaration: class
| enum
class: KEY_CLASS { $$ = "test"; }
enum: KEY_ENUM { $$ = "test"; }

石匠.hpp

#ifndef STONEDRIVER_INCLUDED_HPP
#define STONEDRIVER_INCLUDED_HPP
#include <string>
#include <map>
#include "stone.tab.hh"
class StoneDriver;
//Tell Flex the lexer's prototype ...
#define YY_DECL 
yy::StoneParser::symbol_type yylex (StoneDriver& driver)
// ... and declare it for the parser's sake.
YY_DECL;
//Scans and parses Stone
class StoneDriver
{
public:
//Constructor
StoneDriver();
//Destructor
virtual ~StoneDriver();
std::map<std::string, int> variables;
int result;
// Handling the scanner.
void scan_begin ();
void scan_end ();
bool trace_scanning;
// Run the parser on file F.
// Return 0 on success.
int parse (const std::string& f);
// The name of the file being parsed.
// Used later to pass the file name to the location tracker.
std::string file;
// Whether parser traces should be generated.
bool trace_parsing;
// Error handling.
void error (const yy::location& l, const std::string& m);
void error (const std::string& m);
};//StoneDriver
#endif

石匠.cpp：

#include "StoneDriver.hpp"
#include "stone.tab.hh"
StoneDriver::StoneDriver()
: trace_scanning (false), trace_parsing (false)
{
variables["one"] = 1;
variables["two"] = 2;
}//constructor
StoneDriver::~StoneDriver()
{
}//destructor
int StoneDriver::parse(const std::string &f)
{
file = f;
scan_begin();
yy::StoneParser parser(*this);
#if YYDEBUG
parser.set_debug_level(trace_parsing);
#endif
int res = parser.parse();
scan_end();
return res;
}//parse
void StoneDriver::error(const yy::location& l, const std::string& m)
{
std::cerr << l << ": " << m << std::endl;
}//error
void StoneDriver::error(const std::string& m)
{
std::cerr << m << std::endl;
}//error

溶液： Rici表明，YY_DECL的方法签名应该这样定义：

int yylex (semantic_type* YYLVAL, location_type* YYLLOC, TYPE1 ARG1, ...)

就我而言，魔术线是：

#define YY_DECL int yylex( yy::StoneParser::semantic_type* const lval, yy::StoneParser::location_type* location, StoneDriver& driver )

• yy::是我的 Bison 文件中的命名空间(在我的例子中是 stone.yy)
• StoneParser是 stone.yy 中定义的parser_class_name
• location_type是必需的，因为 stone.yy 具有 %位置 定义。
• StoneDriver&是来自 stone.yy 的解析上下文， 定义为%param { StoneDriver& driver }

感谢您的帮助！