forked from boostorg/iterator
The MPL version is slower to compile and `BOOST_STATIC_ASSERT` is already used in some places. So unify that. This also fixes `Wzero-as-null-pointer-constant` warnings, see https://github.com/boostorg/mpl/pull/75
The MPL version is slower to compile and `BOOST_STATIC_ASSERT` is already used in some places. So unify that. This also fixes `Wzero-as-null-pointer-constant` warnings, see https://github.com/boostorg/mpl/pull/75