Add support for multidispatch in `fn::invoke` and `fn::invoke_r`

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 100.0%. Comparing base (cef2741) to head (715b9f9).

Additional details and impacted files

[](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn) ```diff @@ Coverage Diff @@ ## main #72 +/- ## ======================================= Coverage 100.0% 100.0% ======================================= Files 19 19 Lines 842 850 +8 Branches 121 121 ======================================= + Hits 842 850 +8 ``` | [Files](https://app.codecov.io/gh/libfn/functional/pull/72?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn) | Coverage Δ | | |---|---|---| | [include/functional/and\_then.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Fand_then.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2FuZF90aGVuLmhwcA==) | `100.0% <100.0%> (ø)` | | | [include/functional/choice.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Fchoice.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2Nob2ljZS5ocHA=) | `100.0% <100.0%> (ø)` | | | [include/functional/detail/functional.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Fdetail%2Ffunctional.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2RldGFpbC9mdW5jdGlvbmFsLmhwcA==) | `100.0% <100.0%> (ø)` | | | [include/functional/detail/pack\_impl.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Fdetail%2Fpack_impl.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2RldGFpbC9wYWNrX2ltcGwuaHBw) | `100.0% <100.0%> (ø)` | | | [include/functional/detail/variadic\_union.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Fdetail%2Fvariadic_union.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2RldGFpbC92YXJpYWRpY191bmlvbi5ocHA=) | `100.0% <100.0%> (ø)` | | | [include/functional/expected.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Fexpected.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2V4cGVjdGVkLmhwcA==) | `100.0% <ø> (ø)` | | | [include/functional/fail.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Ffail.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2ZhaWwuaHBw) | `100.0% <100.0%> (ø)` | | | [include/functional/filter.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Ffilter.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2ZpbHRlci5ocHA=) | `100.0% <100.0%> (ø)` | | | [include/functional/functional.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Ffunctional.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2Z1bmN0aW9uYWwuaHBw) | `100.0% <ø> (ø)` | | | [include/functional/functor.hpp](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&filepath=include%2Ffunctional%2Ffunctor.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn#diff-aW5jbHVkZS9mdW5jdGlvbmFsL2Z1bmN0b3IuaHBw) | `100.0% <ø> (ø)` | | | ... and [9 more](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn) | | [](https://app.codecov.io/gh/libfn/functional/pull/72?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=libfn)