Question

我是编程新手，所以我很抱歉这是一个显而易见的问题，但是我在一本书（C ++的创建者使用C ++第二版编程原理和实践， Bjarne Stroustrup）。其中，以下内容用于创建字符串向量：

vector<string> philosopher
    ={"Kant","Plato","Hume","Kierkegaard"};

然而，当通过g ++传递它时，它并不喜欢它。我的代码如下：

#include "std_lib_facilities.h"  //The author's library for his examples

int main()
{
  vector<string>philosopher
    ={"Kant","Plato","Hume","Kierkegaard"};

}

我收到错误编译：

g++ vecttest.cpp -std=c++11
In file included from /usr/local/include/c++/4.9.0/ext/hash_map:60:0,
             from /usr/include/std_lib_facilities.h:34,
             from vecttest.cpp:1:
/usr/local/include/c++/4.9.0/backward/backward_warning.h:32:2: warning: #warning 
This file includes at least one deprecated or antiquated header which may 
be removed without further notice at a future date. Please use a 
non-deprecated interface with equivalent functionality instead. For a listing     
of replacement headers and interfaces, consult the file backward_warning.h. 
To disable this warning use -Wno-deprecated. [-Wcpp]
#warning \
^
In file included from /usr/local/include/c++/4.9.0/locale:41:0,
             from /usr/local/include/c++/4.9.0/iomanip:43,
             from /usr/include/std_lib_facilities.h:212,
             from vecttest.cpp:1:
/usr/local/include/c++/4.9.0/bits/locale_facets_nonio.h:1869:5: error: 
template-id  ‘do_get<>’ for 
‘String std::messages<char>::do_get(std::messages_base::catalog, int, int, 
const String&) const’ does not match any template declaration
 messages<char>::do_get(catalog, int, int, const string&) const;
 ^
/usr/local/include/c++/4.9.0/bits/locale_facets_nonio.h:1869:62: note: 
saw 1 ‘template<>’, need 2 for specializing a member function template
 messages<char>::do_get(catalog, int, int, const string&) const;
                                                          ^
vecttest.cpp: In function ‘int main()’:
vecttest.cpp:8:42: error: could not convert ‘{"Kant", "Plato", 
"Hume","Kierkegaard"}’from ‘<brace-enclosed initializer list>’ to ‘Vector<String>’
 ={"Kant","Plato","Hume","Kierkegaard"};

我想也许我的GCC版本较旧（它的版本是4.7）所以我将其更新为4.9：

g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-unknown-linux-gnu/4.9.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-4.9.0/configure
Thread model: posix
gcc version 4.9.0 (GCC)

我出错的任何想法？

非常感谢你的帮助。

Answer 1

您使用此std_lib_facilities.h时出错了。 Looking at it online，它显示：

template< class T> struct Vector : public std::vector<T> {
    ...
};

// disgusting macro hack to get a range checked vector:
#define vector Vector

不幸的是，这个自定义Vector模板类缺少std::vector确实拥有的一些构造函数。

直接使用std::vector即可使用。它在GCC 4.4和更新版本中得到了支持。

注意：要使用std::vector，您需要确保根本不使用std_lib_facilities.h，或使用#undef vector。宏定义存在问题，并且不关注命名空间，因此std::vector将成为不存在的std::Vector。

注2：T.C。正确地评论string也存在类似问题：改为使用std::string。

带有大括号括起初始化列表的C ++ 11 g ++

1 个答案: