Implement N3654 - Quoted Strings Library Proposal

2013-06-08  Ed Smith-Rowland  <3dw4rd@verizon.net>

	Implement N3654 - Quoted Strings Library Proposal
	* include/std/iomanip: Add quoted(String, Char delim, Char escape)
	manipulators and supporting machinery in c++1y mode.
	* testsuite/27_io/manipulators/standard/char/quoted.cc: New.
	* testsuite/27_io/manipulators/standard/wchar_t/quoted.cc: New.

From-SVN: r199860

1 files changed, 154 insertions, 1 deletions

diff --git a/libstdc++-v3/include/std/iomanip b/libstdc++-v3/include/std/iomanip
index 599d220..47284e8 100644
--- a/libstdc++-v3/include/std/iomanip
+++ b/libstdc++-v3/include/std/iomanip
@@ -334,7 +334,160 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       return __os; 
     }
 
-#endif
+#if __cplusplus > 201103L
+
+  namespace __detail {
+
+    /**
+     * @brief Struct for delimited strings.
+     *        The left and right delimiters can be different.
+     */
+    template<typename _String, typename _CharT>
+      struct _Quoted_string
+      {
+	static_assert(is_reference<_String>::value
+		   || is_pointer<_String>::value,
+		      "String type must be pointer or reference");
+
+	_Quoted_string(_String __str, _CharT __del, _CharT __esc)
+	: _M_string(__str), _M_delim{__del}, _M_escape{__esc}
+	{ }
+
+	_Quoted_string&
+	operator=(_Quoted_string&) = delete;
+
+	_String _M_string;
+	_CharT _M_delim;
+	_CharT _M_escape;
+      };
+
+    /**
+     * @brief Inserter for delimited strings.
+     *        The left and right delimiters can be different.
+     */
+    template<typename _CharT, typename _Traits>
+      auto&
+      operator<<(std::basic_ostream<_CharT, _Traits>& __os,
+		 const _Quoted_string<const _CharT*, _CharT>& __str)
+      {
+	__os << __str._M_delim;
+	for (const _CharT* __c = __str._M_string; *__c; ++__c)
+	  {
+	    if (*__c == __str._M_delim || *__c == __str._M_escape)
+	      __os << __str._M_escape;
+	    __os << *__c;
+	  }
+	__os << __str._M_delim;
+
+	return __os;
+      }
+
+    /**
+     * @brief Inserter for delimited strings.
+     *        The left and right delimiters can be different.
+     */
+    template<typename _CharT, typename _Traits, typename _String>
+      auto&
+      operator<<(std::basic_ostream<_CharT, _Traits>& __os,
+		 const _Quoted_string<_String, _CharT>& __str)
+      {
+	__os << __str._M_delim;
+	for (auto& __c : __str._M_string)
+	  {
+	    if (__c == __str._M_delim || __c == __str._M_escape)
+	      __os << __str._M_escape;
+	    __os << __c;
+	  }
+	__os << __str._M_delim;
+
+	return __os;
+      }
+
+    /**
+     * @brief Extractor for delimited strings.
+     *        The left and right delimiters can be different.
+     */
+    template<typename _CharT, typename _Traits, typename _Alloc>
+      auto&
+      operator>>(std::basic_istream<_CharT, _Traits>& __is,
+		 const _Quoted_string<basic_string<_CharT, _Traits, _Alloc>&,
+				      _CharT>& __str)
+      {
+	__str._M_string.clear();
+
+	_CharT __c;
+	__is >> __c;
+	if (!__is.good())
+	  return __is;
+	if (__c != __str._M_delim)
+	  {
+	    __is.unget();
+	    __is >> __str._M_string;
+	    return __is;
+	  }
+	std::ios_base::fmtflags __flags
+	  = __is.flags(__is.flags() & ~std::ios_base::skipws);
+	do
+	  {
+	    __is >> __c;
+	    if (!__is.good())
+	      break;
+	    if (__c == __str._M_escape)
+	      {
+		__is >> __c;
+		if (!__is.good())
+		  break;
+	      }
+	    else if (__c == __str._M_delim)
+	      break;
+	    __str._M_string += __c;
+	  }
+	while (true);
+	__is.setf(__flags);
+
+	return __is;
+      }
+
+  } // namespace __detail
+
+  /**
+   * @brief Manipulator for quoted strings.
+   * @param __str    String to quote.
+   * @param __delim  Character to quote string with.
+   * @param __escape Escape character to escape itself or quote character.
+   */
+  template<typename _CharT>
+    inline auto
+    quoted(const _CharT* __string,
+	   _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
+    {
+      return __detail::_Quoted_string<const _CharT*, _CharT>(__string, __delim,
+							     __escape);
+    }
+
+  template<typename _CharT, typename _Traits, typename _Alloc>
+    inline auto
+    quoted(const basic_string<_CharT, _Traits, _Alloc>& __string,
+	   _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
+    {
+      return __detail::_Quoted_string<
+			const basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
+				__string, __delim, __escape);
+    }
+
+  template<typename _CharT, typename _Traits, typename _Alloc>
+    inline auto
+    quoted(basic_string<_CharT, _Traits, _Alloc>& __string,
+	   _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
+    {
+      return __detail::_Quoted_string<
+			basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
+				__string, __delim, __escape);
+    }
+
+#endif // __cplusplus > 201103L
+
+#endif // __cplusplus >= 201103L
 
   // Inhibit implicit instantiations for required instantiations,
   // which are defined via explicit instantiations elsewhere.