- 'if constexpr (...)'
* instead of std::enable_if
* terminate template recursion
* compile-time elimination of code
- use C++14 '_t', '_v' versions,
eg, std::is_integral_v<T> instead of std::is_integral<T>::value
- std::begin, std::end, std::void_t instead of prev stdFoam versions
- provide is_contiguous_v<..> as short form of is_contiguous<..>::value
with the additional benefit of removing any cv qualifiers.
ENH: include is_rotational_vectorspace trait
- tests for vector-space and nComponents > 1 (ie, not sphericalTensor)
ENH: improve robustness of pTraits_.. tests by removing cv qualifiers
- used low-level MPI gather, but the wrapping routine contains an
additional safety check for is_contiguous which is not defined for
various std::pair<..> combination.
So std::pair<label,vector> (which is actually contiguous, but not
declared as is_contiguous) would falsely trip the check.
Avoid by simply gathering unbundled values instead.
- change contiguous from a series of global functions to separate
templated traits classes:
- is_contiguous
- is_contiguous_label
- is_contiguous_scalar
The static constexpr 'value' and a constexpr conversion operator
allow use in template expressions. The change also makes it much
easier to define general traits and to inherit from them.
The is_contiguous_label and is_contiguous_scalar are special traits
for handling data of homogeneous components of the respective types.
