c++ - 错误 C2143 : syntax error : missing ';' before '*' (haven't found solution)

Question

我的代码中有一个编译错误:

#include <iostream>
#include <vector>
#include "command.h"

extern std::istream *instream;
extern std::vector<command> commands;

这是 command.h 头文件:

#define CMD_RETURN_TYPE_NONE 0
#define CMD_RETURN_TYPE_STRING 1
#define CMD_RETURN_TYPE_CHAR 2
#define CMD_RETURN_TYPE_INT 3
class command {
    public:
        virtual int getReturnType(void);
        virtual char getOpName(void);
        virtual void* call(void);
}

抛出下一个编译错误

1>------ Build started: Project: MyFirstCPPApp, Configuration: Debug Win32 ------
1>Compiling...
1>MyFirstCPPApp.cpp
1>e:\anton\msvc++ projects\myfirstcppapp\myfirstcppapp\MyFirstCPPApp.h(5) : error C2143: syntax error : missing ';' before '*'
1>e:\anton\msvc++ projects\myfirstcppapp\myfirstcppapp\MyFirstCPPApp.h(5) : error C2377: 'std::istream' : redefinition; typedef cannot be overloaded with any other symbol
1>        E:\Anton\MSVS2008Express\VC\include\iosfwd(707) : see declaration of 'std::istream'
1>e:\anton\msvc++ projects\myfirstcppapp\myfirstcppapp\MyFirstCPPApp.h(5) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>.\MyFirstCPPApp.cpp(4) : error C2039: 'get' : is not a member of 'System::Int32'
1>        c:\windows\microsoft.net\framework\v2.0.50727\mscorlib.dll : see declaration of 'System::Int32'
1>.\MyFirstCPPApp.cpp(7) : error C3861: 'callCmd': identifier not found
1>.\MyFirstCPPApp.cpp(11) : error C2440: '=' : cannot convert from 'std::istream *' to 'int *'
1>        Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
1>Build log was saved at "file://e:\Anton\MSVC++ Projects\MyFirstCPPApp\MyFirstCPPApp\Debug\BuildLog.htm"
1>MyFirstCPPApp - 6 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

我还没有找到解决方案，如何解决？

Answer 1

失踪;之后:

类命令{...;

右括号和分号(表示行的结尾)之间的任何内容都将被解析为属于此类的可选对象列表。

因此，有必要在类定义之后添加分号，这样编译器就知道这个类定义之后的任何内容都不是对象列表的一部分。