C++ L "whatever" -> 绳子 -> basic_string<T>

Question

我正在为解析器编写一个"字符串分割器"，我希望能够同时使用char和wchar_t。我有以下方法:

static void tokenize(const basic_string<T> &, vector<CToken> &);

我想给它一个宽字符串解析:

vector<CToken> tTokens;
CTokenizer<wstring>::tokenize(L"if(i == 0) { print i + 2; } else { return; }", tTokens);

我也试过:

vector<CToken> tTokens;
const wstring sCode = L"if(i == 0) { print i + 2; } else { return; }";
CTokenizer<wstring>::tokenize(sCode, tTokens);

所以我假设有一些我不理解的模板。我能做些什么呢?

谢谢你的帮助!

编辑:这是我的构建日志:

1>------ Build started: Project: c_parser, Configuration: Debug Win32 ------
1>  Parsercpp.cpp
1>c:usersvirusdocumentsvisual studio 2012projectsc_parserc_parserparsercpp.cpp(44): error C2958: the left parenthesis '(' found at 'c:usersvirusdocumentsvisual studio 2012projectsc_parserc_parserparsercpp.cpp(38)' was not matched correctly
1>c:program files (x86)microsoft visual studio 11.0vcincludexstring(529): error C2621: member 'std::_String_val<_Val_types>::_Bxty::_Buf' of union 'std::_String_val<_Val_types>::_Bxty' has copy constructor
1>          with
1>          [
1>              _Val_types=std::_Simple_types<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t>>>
1>          ]
1>          c:program files (x86)microsoft visual studio 11.0vcincludexstring(532) : see reference to class template instantiation 'std::_String_val<_Val_types>::_Bxty' being compiled
1>          with
1>          [
1>              _Val_types=std::_Simple_types<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t>>>
1>          ]
1>          c:program files (x86)microsoft visual studio 11.0vcincludexstring(627) : see reference to class template instantiation 'std::_String_val<_Val_types>' being compiled
1>          with
1>          [
1>              _Val_types=std::_Simple_types<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t>>>
1>          ]
1>          c:program files (x86)microsoft visual studio 11.0vcincludexstring(700) : see reference to class template instantiation 'std::_String_alloc<_Al_has_storage,_Alloc_types>' being compiled
1>          with
1>          [
1>              _Al_has_storage=false,
1>              _Alloc_types=std::_String_base_types<std::wstring,std::allocator<std::wstring>>
1>          ]
1>          c:usersvirusdocumentsvisual studio 2012projectsc_parserc_parserparsercpp.cpp(104) : see reference to class template instantiation 'std::basic_string<_Elem>' being compiled
1>          with
1>          [
1>              _Elem=std::wstring
1>          ]
1>c:usersvirusdocumentsvisual studio 2012projectsc_parserc_parserparsercpp.cpp(104): error C2664: 'nsParser::CTokenizer<T>::tokenize' : cannot convert parameter 1 from 'const std::wstring' to 'const std::basic_string<_Elem> &'
1>          with
1>          [
1>              T=std::wstring
1>          ]
1>          and
1>          [
1>              _Elem=std::wstring
1>          ]
1>          Reason: cannot convert from 'const std::wstring' to 'const std::basic_string<_Elem>'
1>          with
1>          [
1>              _Elem=std::wstring
1>          ]
1>          No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

编辑:

template<class T>
class CTokenizer
{
public:
    static vector<T> s_tKeywords;
public:
    static void tokenize(const basic_string<T> &, vector<CToken> &);
};

parser.cpp中的代码就是上面的代码:

vector<CToken> tTokens;
const wstring sCode = L"if(i == 0) { print i + 2; } else { return; }";
CTokenizer<wstring>::tokenize(sCode, tTokens);

Answer 1

应该实例化CTokenizer<wchar_t>，而不是CTokenizer<std::wstring>。你这样做，tokenize()的签名变成

static void tokenize(const basic_string<wstring> &, vector<CToken> &);

Answer 2

将tokenize的声明更改为

static void tokenize(const T &, vector<CToken> &);

或调用

CTokenizer<wchar_t>::tokenize(L"if(i == 0) { print i + 2; } else { return; }", tTokens);

---

在注释后编辑:然后使用"or"部分(而不是"either")…

由于T是"char类型"(而不是字符串类型)，我建议您将其重命名为有意义的东西。

获取第二次编辑的代码，在这些更改之后，类看起来像:

template<class CharT>
class CTokenizer
{
public:
    static vector< basic_string<CharT> > s_tKeywords;
public:
    static void tokenize(const basic_string<CharT> &, vector<CToken> &);
};

，然后调用tokenize，就像我上面写的那样(使用wchar_t，而不是wstring作为模板类型参数)。(wstring只是basic_string<wchar_t>的类型别名)