Title
Remove redundant deduction guides from standard library
Status
c++20
Section
[refwrap][thread.lock.guard] [thread.lock.scoped][thread.lock.unique][thread.lock.shared]
Submitter
Mike Spertus

Created on 2017-06-15.00:00:00 last changed 3 months ago

Messages

Date: 2017-07-12.01:30:31

Proposed resolution:

This wording is relative to N4659.

  1. Edit [refwrap], end of class template reference_wrapper synopsis, as indicated:

    template<class T>
      reference_wrapper(reference_wrapper<T>) -> reference_wrapper<T>;
    
  2. Edit [thread.lock.guard], end of class template lock_guard synopsis, as indicated:

    template<class Mutex> lock_guard(lock_guard<Mutex>) -> lock_guard<Mutex>;
    
  3. Edit [thread.lock.scoped], end of class template scoped_lock synopsis, as indicated:

    template<class... MutexTypes>
      scoped_lock(scoped_lock<MutexTypes...>) -> scoped_lock<MutexTypes...>;
    
  4. Edit [thread.lock.unique], end of class template unique_lock synopsis, as indicated:

    template<class Mutex> unique_lock(unique_lock<Mutex>) -> unique_lock<Mutex>;
    
  5. Edit [thread.lock.shared], end of class template shared_lock synopsis, as indicated:

    template<class Mutex> shared_lock(shared_lock<Mutex>) -> shared_lock<Mutex>;
    
Date: 2017-07-12.01:30:31

[ 2017-07 Toronto Monday issue prioritization ]

Priority 0; move to Ready

Date: 2017-06-15.00:00:00

There are several deduction guides added to the standard library by P0433R2 that have no effect probably because LWG had not considered late changes to core wording that automatically adds a "copy deduction candidate" ([over.match.class.deduct]) that renders these explicit guides moot.

History
Date User Action Args
2021-02-25 10:48:01adminsetstatus: wp -> c++20
2017-11-13 19:01:36adminsetstatus: voting -> wp
2017-10-17 18:34:55adminsetstatus: ready -> voting
2017-07-12 01:30:31adminsetmessages: + msg9346
2017-07-12 01:30:31adminsetstatus: new -> ready
2017-06-16 19:21:06adminsetmessages: + msg9271
2017-06-15 00:00:00admincreate