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我正在尝试按照本教程了解 C++11 中的正则表达式。当我尝试编译这个小代码示例时，我得到了这些错误

clang++ -std=c++0x test.cpp -o test
In file included from test.cpp:3:
In file included from /usr/include/c++/4.6/regex:55:
/usr/include/c++/4.6/bits/regex_constants.h:196:36: error: constexpr variable
      'match_default' must be initialized by a constant expression
  static constexpr match_flag_type match_default     = 0;
                                   ^~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:203:36: error: constexpr variable
      'match_not_bol' must be initialized by a constant expression
  static constexpr match_flag_type match_not_bol     = 1 << _S_not_bol;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:210:36: error: constexpr variable
      'match_not_eol' must be initialized by a constant expression
  static constexpr match_flag_type match_not_eol     = 1 << _S_not_eol;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:216:36: error: constexpr variable
      'match_not_bow' must be initialized by a constant expression
  static constexpr match_flag_type match_not_bow     = 1 << _S_not_bow;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:222:36: error: constexpr variable
      'match_not_eow' must be initialized by a constant expression
  static constexpr match_flag_type match_not_eow     = 1 << _S_not_eow;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:228:36: error: constexpr variable
      'match_any' must be initialized by a constant expression
  static constexpr match_flag_type match_any         = 1 << _S_any;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:233:36: error: constexpr variable
      'match_not_null' must be initialized by a constant expression
  static constexpr match_flag_type match_not_null    = 1 << _S_not_null;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:238:36: error: constexpr variable
      'match_continuous' must be initialized by a constant expression
  static constexpr match_flag_type match_continuous  = 1 << _S_continuous;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:245:36: error: constexpr variable
      'match_prev_avail' must be initialized by a constant expression
  static constexpr match_flag_type match_prev_avail  = 1 << _S_prev_avail;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:273:36: error: constexpr variable
      'format_default' must be initialized by a constant expression
  static constexpr match_flag_type format_default    = 0;
                                   ^~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:281:36: error: constexpr variable
      'format_sed' must be initialized by a constant expression
  static constexpr match_flag_type format_sed        = 1 << _S_sed;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:288:36: error: constexpr variable
      'format_no_copy' must be initialized by a constant expression
  static constexpr match_flag_type format_no_copy    = 1 << _S_no_copy;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/4.6/bits/regex_constants.h:294:36: error: constexpr variable
      'format_first_only' must be initialized by a constant expression
  static constexpr match_flag_type format_first_only = 1 << _S_first_only;
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
13 errors generated.

怎么了？

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1 回答 1

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默认情况下，clang 使用 gcc 的标准 C++ 库 - libstdc++。它仍然不支持正则表达式。您可以尝试使用 libc++ - 另一个支持所有 C++11 的标准库实现。clang++ -stdlib=libc++ source.cpp -o source使用教程中的第一个示例代码对我来说非常适合。

但是，将 libc++ 和 libstdc++ 库/可执行文件链接在一起并不是一个好主意——它们是不兼容的。

于 2013-06-20T19:15:48.160 回答