remove boost dependencies for the library

[marehr]

• boost program options
• boost pp (for f2f) https://github.com/noma/ham/blob/7466a17f8d34ae107cb88bcb8b2a84da25a1b23d/include/ham/functor/function.hpp#L76-L122

[noma]

Would shipping all boost dependencies in thirdparty and integrating them directly into the CMake build be an option for you?

Boost PP is header only, so shouldn't matter anyways.

[marehr]

We could change f2f in the following ways:

• We use the original definition of f2f

  #define f2f(function_ptr, ...) ham::function<decltype(function_ptr), function_ptr>(__VA_ARGS__)
  

  and add f2f_zero for zero arguments

  #define f2f_zero(function_ptr) ham::function<decltype(function_ptr), function_ptr>()
  

  :+1: f2f stays the same :+1: f2f can be used with zero arguments if the user does not bother about the warning :-1: Introduces a new "name"

• We change the definition of f2f

  #define f2f(function_ptr) ham::function<decltype(function_ptr), function_ptr>
  

  invocation would change to

  f2f(&function)(arg0, arg1, arg2);
  

  :+1: f2f now clearly differentiate between type and variables :-1: breaks backwards compatibility

[marehr]

Boost PP is header only, so shouldn't matter anyways.

Yep is also an viable option.

[noma]

Note: as discussed yesterday for C++ 17:

template<auto function_ptr>
using f2f = ham::function<decltype(function_ptr), function_ptr>;

f2f<function>(args...)

[noma]

So we have:

f2f(function, args...); // original syntax: BOOST_PP_OVERLOAD for portability and no compiler warnings
f2f(function)(args...); // C++11, still Macros, but nor variadic macro necessary
f2f<function>(args...); // C++17, no macros :-)

TODO: decide what to offer, naming to avoid conflicts, and whether or not to drop backward compatibility

[noma]

With respect to the standard library's std::functionand std::bind are closest relatives, f2f is very similar to bind, while the result is close to std::function:

For C++17 I'd propose the following:

• remove f2f alltogether to get rid of the macro and not overload the old construct with something new
  • maybe add a dummy function instead of the macro and mark it deprecated to generate useful compiler errors for old code
• introduce ham::function instead

ham::sync(ham::function<function_ptr>(arg1, arg2, ...)) // 3rd from above

@marehr opinions?

[marehr]

sounds good.

[noma]

Removed Boost Program Options in favor of header only CLI11 lib. Only Boost PP remains, but is header only and shipped in thirdparty folder, for C++11/14 compatibility.