regex: learning to crawl

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@106882 91177308-0d34-0410-b5e6-96231b3b80d8

test/re/re.regex/re.regex.construct/ptr_flg.pass.cpp

@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <regex>
+
+// template <class charT, class traits = regex_traits<charT>> class basic_regex;
+
+// basic_regex(const charT* p, flag_type f = regex_constants::ECMAScript);
+
+#include <regex>
+#include <cassert>
+
+template <class CharT>
+void
+test(const CharT* p, std::regex_constants::syntax_option_type f, unsigned mc)
+{
+    std::basic_regex<CharT> r(p, f);
+    assert(r.flags() == f);
+    assert(r.mark_count() == mc);
+}
+
+int main()
+{
+    test("", std::regex_constants::basic, 0);
+    test("\\(a\\)", std::regex_constants::basic, 1);
+    test("\\(a[bc]\\)", std::regex_constants::basic, 1);
+    test("\\(a\\([bc]\\)\\)", std::regex_constants::basic, 2);
+    test("(a([bc]))", std::regex_constants::basic, 0);
+}