Re: [boost] What to do about std::binary_function and std::unary_function?

On 05.05.2016 21:18, Nick Matteo wrote:

3) A modification of approach 2: instead of manually adding the typedefs everywhere, make a base class to provide the typedefs somewhere in Boost. Then replace inheritance from std::binary_function with inheritance from boost::binary_function.

3a) Provide boost::binary_function, which inherits std::binary_function if it is available, and reimplements std::binary_function otherwise. This seems like the least intrusive, most backwards-compatible solution. Any old code that (for some pathological reason) depends on the use of std::binary_function will continue to function so long as std::binary_function exists. Any code that merely depends on the typedefs that std::binary_function provides will continue to function indefinitely. All existing boost code can be updated with a simple search-and-replace, with no decrease in code readability or compactness. And moving from (3a) to (3) would be a simple change to a single file, should this change ever become necessary or desirable. -- Rainer Deyke (rainerd@eldwood.com)