Adding logical implication to boost

From: Ivan Matek (libbooze_at_[hidden])
Date: 2025-01-04 19:43:05

Hi everyone,

there has been a recent proposal to add logical implication to C++ as an
operator.
github tracking issue <https://github.com/cplusplus/papers/issues/1641>
P2971R2
<https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/p2971r2.pdf>

For a video description you can see this talk
<https://youtu.be/bgyY3x8y4PE?feature=shared&t=1470> by Walter(it is only
few minutes, not entire talk).

While I agree with concerns mentioned on the issue, i.e. using a
*precious *token
=> on rarely used functionality I do think that implementing a simple
function helper is reasonable.

Poll in issue shows that this is also likely standardization future.
POLL: We agree with adding a function object logical_implication (tentative
name, akin logical_and, `logical_or’).

SF   F   N   A  SA
 9  12   3   0   0

As for if it is worthwhile to add this simple logic to boost instead of
people just writing their own I will just say I would prefer to have
something named in boost instead of people reinventing same thing many
times in their projects. I have used it few times in my career, so quite
rarely, but again that means I have used it much more often than 80+% of
algorithms in <algorithm> header.

As for location I presume best place would be Boost.Algorithm although you
could say that Boost.Core can be a candidate because it is a basic
operation and would benefit from shorter namespace. I would be still
inclined against this since I have seen core/util/common become huge in
many codebases I have worked in.

I have tried to check if this already exists in Boost; all I found was an
example in Boost.Hana.