* Added c++17 test configurations for clang5.0 and clang6.0
* Removed explicit not_null constructor, sloppy_not_null, added strict_not_null
We added explicit not_null constructor in version 2.0.0.
It proved very difficult to switch to the new version for
large code bases that adopted previous versions of gsl,
due to not_null used extensively in the code. Still, using
explicit constructor is very benefitial for new code, since
it encorages better API design and make null checks intentional.
To resolve the issue, this change:
- removes explicit keyword from not_null constructor
- removes unneded sloppy_not_null type
- adds strict_not_null type to behave the same way as v2 not_null
- updates tests
* Removed explicit not_null constructor, sloppy_not_null, added strict_not_null
We added explicit not_null constructor in version 2.0.0.
It proved very difficult to switch to the new version for
large code bases that adopted previous versions of gsl,
due to not_null used extensively in the code. Still, using
explicit constructor is very benefitial for new code, since
it encorages better API design and make null checks intentional.
To resolve the issue, this change:
- removes explicit keyword from not_null constructor
- removes unneded sloppy_not_null type
- adds strict_not_null type to behave the same way as v2 not_null
- updates tests
* fixed build break for gcc7
* added more tests
* added more non-compiling tests
* Addressed PR comments and suppressed a code analysis warning
* Fixed test failure in not_null tests
