Proposed resolution:

Change [re.regex]:

template <class charT,
          class traits = regex_traits<charT> >
class basic_regex {
  ...
  basic_regex& operator=(const charT* ptr);
  basic_regex& operator=(initializer_list<charT> il);
  template <class ST, class SA>
    basic_regex& operator=(const basic_string<charT, ST, SA>& p);
  ...
};

Add in [re.regex.construct]:

-20- ...

basic_regex& operator=(initializer_list<charT> il);

-21- Effects: returns assign(il.begin(), il.end());

[ Batavia (2009-05): ]

UK 317 asks for both assignment and constructor, but the requested constructor is already present in the current Working Paper. We agree with the proposed resolution. Move to Tentatively Ready.

Addresses UK 317 and JP 74

UK 317:

basic_string has both a constructor and an assignment operator that accepts an initializer list, basic_regex should have the same.

JP 74:

basic_regex & operator= (initializer_list<T>); is not defined.