Implement deduction guides for basic_regex

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@333050 91177308-0d34-0410-b5e6-96231b3b80d8

include/regex

@@ -192,6 +192,11 @@ public:
     void swap(basic_regex&);
 };
 
+template<class ForwardIterator>
+basic_regex(ForwardIterator, ForwardIterator,
+            regex_constants::syntax_option_type = regex_constants::ECMAScript)
+    -> basic_regex<typename iterator_traits<ForwardIterator>::value_type>; // C++17
+
 typedef basic_regex<char>    regex;
 typedef basic_regex<wchar_t> wregex;
 
@@ -2922,6 +2927,15 @@ private:
     template <class, class> friend class __lookahead;
 };
 
+#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
+template <class _ForwardIterator,
+          class = typename enable_if<__is_forward_iterator<_ForwardIterator>::value, nullptr_t>::type
+>
+basic_regex(_ForwardIterator, _ForwardIterator,
+            regex_constants::syntax_option_type = regex_constants::ECMAScript)
+    -> basic_regex<typename iterator_traits<_ForwardIterator>::value_type>;
+#endif
+
 template <class _CharT, class _Traits>
     const regex_constants::syntax_option_type basic_regex<_CharT, _Traits>::icase;
 template <class _CharT, class _Traits>

test/std/re/re.regex/re.regex.construct/deduct.fail.cpp

@@ -0,0 +1,45 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <regex>
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// UNSUPPORTED: libcpp-no-deduction-guides
+
+
+// template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+//    vector(InputIterator, InputIterator, Allocator = Allocator())
+//    -> vector<typename iterator_traits<InputIterator>::value_type, Allocator>;
+//
+
+
+#include <regex>
+#include <string>
+#include <iterator>
+#include <cassert>
+#include <cstddef>
+
+
+int main()
+{  
+//  Test the explicit deduction guides
+    {
+//	basic_regex(ForwardIterator, ForwardIterator)
+//  <int> is not an iterator
+    std::basic_regex re(23, 34);   // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'basic_regex'}}
+    }
+
+    {
+//	basic_regex(ForwardIterator, ForwardIterator, flag_type)
+//  <double> is not an iterator
+    std::basic_regex re(23.0, 34.0, std::regex_constants::basic);   // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'basic_regex'}}
+    }
+
+//  Test the implicit deduction guides
+
+}

test/std/re/re.regex/re.regex.construct/deduct.pass.cpp

@@ -0,0 +1,137 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <regex>
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// UNSUPPORTED: libcpp-no-deduction-guides
+
+
+// template<class ForwardIterator>
+// basic_regex(ForwardIterator, ForwardIterator,
+//             regex_constants::syntax_option_type = regex_constants::ECMAScript)
+// -> basic_regex<typename iterator_traits<ForwardIterator>::value_type>;
+        
+
+#include <regex>
+#include <string>
+#include <iterator>
+#include <cassert>
+#include <cstddef>
+
+#include "test_macros.h"
+#include "test_iterators.h"
+#include "test_allocator.h"
+
+using namespace std::literals;
+
+struct A {};
+
+int main()
+{
+  
+//  Test the explicit deduction guides
+    {
+//  basic_regex(ForwardIterator, ForwardIterator)
+    std::string s1("\\(a\\)");
+    std::basic_regex re(s1.begin(), s1.end());
+
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<char>>, "");
+    assert(re.flags() == std::regex_constants::ECMAScript);
+    assert(re.mark_count() == 0);
+    }
+
+    {
+    std::wstring s1(L"\\(a\\)");
+    std::basic_regex re(s1.begin(), s1.end(), std::regex_constants::basic);
+
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<wchar_t>>, "");
+    assert(re.flags() == std::regex_constants::basic);
+    assert(re.mark_count() == 1);
+    }
+    
+//  Test the implicit deduction guides
+    {
+//  basic_regex(string);
+    std::basic_regex re("(a([bc]))"s);
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<char>>, "");
+    assert(re.flags() == std::regex_constants::ECMAScript);
+    assert(re.mark_count() == 2);
+    }
+
+    {
+//  basic_regex(string, flag_type);
+    std::basic_regex re(L"(a([bc]))"s, std::regex_constants::awk);
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<wchar_t>>, "");
+    assert(re.flags() == std::regex_constants::awk);
+    assert(re.mark_count() == 2);
+    }
+
+    {
+//  basic_regex(const charT*);
+    std::basic_regex re("ABCDE");
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<char>>, "");
+    assert(re.flags() == std::regex_constants::ECMAScript);
+    assert(re.mark_count() == 0);
+    }
+
+    {
+//  basic_regex(const charT*, flag_type);
+    std::basic_regex re(L"ABCDE", std::regex_constants::grep);
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<wchar_t>>, "");
+    assert(re.flags() == std::regex_constants::grep);
+    assert(re.mark_count() == 0);
+    }
+    
+    {
+//  basic_regex(const charT*, size_t);
+    std::basic_regex re("ABCDEDEF", 7);
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<char>>, "");
+    assert(re.flags() == std::regex_constants::ECMAScript);
+    assert(re.mark_count() == 0);
+    }
+
+    {
+//  basic_regex(const charT*, size_t, flag_type);
+    std::basic_regex re(L"ABCDEDEF", 8, std::regex_constants::awk);
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<wchar_t>>, "");
+    assert(re.flags() == std::regex_constants::awk);
+    assert(re.mark_count() == 0);
+    }
+
+    {
+//  basic_regex(const basic_regex &);
+    std::basic_regex<char> source;
+    std::basic_regex re(source);
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<char>>, "");
+    assert(re.flags() == source.flags());
+    assert(re.mark_count() == source.mark_count());
+    }
+
+    {
+//  template<class ST, class SA>
+//         explicit basic_regex(const basic_string<charT, ST, SA>& p,
+//                              flag_type f = regex_constants::ECMAScript);
+    }
+
+    {
+//  basic_regex(initializer_list);
+    std::basic_regex re({'A', 'B', 'F', 'E', 'D'});
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<char>>, "");
+    assert(re.flags() == std::regex_constants::ECMAScript);
+    assert(re.mark_count() == 0);
+    }
+
+    {
+//  basic_regex(initializer_list, flag_type);
+    std::basic_regex re({L'A', L'B', L'F', L'E', L'D'}, std::regex_constants::grep);
+    static_assert(std::is_same_v<decltype(re), std::basic_regex<wchar_t>>, "");
+    assert(re.flags() == std::regex_constants::grep);
+    assert(re.mark_count() == 0);
+    }
+}