////
Copyright 2021 Peter Dimov
Distributed under the Boost Software License, Version 1.0.
https://www.boost.org/LICENSE_1_0.txt
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[#changelog]
# Revision History
:idprefix:

## Changes in 1.78.0

* Added special cases in `operator<<` and `operator>>` when
  the first argument is a stream, to allow `std::cout << _1`.
* Added `operator\->*`.
* Added `first`, `second`.
