Eric Fiselier ea10d2477a [libcxx] Add <experimental/tuple> header for LFTS. ... Summary: This patch adds the `<experimental/tuple>` header (almost) as specified in the latest draft of the library fundamentals TS. The main changes in this patch are: 1. Added variable template `tuple_size_v` 2. Added function `apply(Func &&, Tuple &&)`. 3. Changed `__invoke` to be `_LIBCPP_CONSTEXPR_AFTER_CXX11`. The `apply(...)` implementation uses `__invoke` to invoke the given function. `__invoke` already provides the required functionality. Using `__invoke` also allows `apply` to be used on pointers to member function/objects as an extension. In order to facilitate this `__invoke` has to be marked `constexpr`. Test Plan: Each new feature was tested. The test cases for `tuple_size_v` are as follows: 1. tuple_size_v.pass.cpp - Check `tuple_size_v` on cv qualified tuples, pairs and arrays. 2. tuple_size_v.fail.cpp - Test on reference type. 3. tuple_size_v_2.fail.cpp - Test on non-tuple 4. tuple_size_v_3.fail.cpp - Test on pointer type. The test cases for tuple.apply are as follows: 1. arg_type.pass.cpp - Ensure that ref/pointer/cv qualified types are properly passed. 2. constexpr_types.pass.cpp - Ensure constexpr evaluation of apply is possible for `tuple` and `pair`. 3. extended_types.pass.cpp - Test apply on function types permitted by extension. 4. large_arity.pass.cpp - Test that apply can evaluated on tuples and arrays with large sizes. 5. ref_qualifiers.pass.cpp - Test that apply respects ref qualified functions. 6. return_type.pass.cpp - Test that apply returns the proper type. 7. types.pass.cpp - Test apply on function types as required by LFTS. Reviewers: mclow.lists Reviewed By: mclow.lists Subscribers: cfe-commits Differential Revision: http://reviews.llvm.org/D4512 llvm-svn: 232515		2015-03-17 18:28:14 +00:00
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__config	Add pragma system header to some experimental headers and add newlines to files.	2015-02-10 17:32:49 +00:00
chrono	Define a new macro: _LIBCPP_HAS_NO_VARIABLE_TEMPLATES and use it. No functionality change.	2015-03-17 15:30:22 +00:00
dynarray	Handle function name conflicts in _LIBCPP_MSVCRT mode	2015-02-13 22:15:32 +00:00
optional	Add all the relational operators to std::experimental::optional. Also update bad_optional_access to match the Library Fundamentals draft standard. This is not all of the upcoming changes to optional, though.	2014-12-09 14:49:17 +00:00
ratio	Define a new macro: _LIBCPP_HAS_NO_VARIABLE_TEMPLATES and use it. No functionality change.	2015-03-17 15:30:22 +00:00
string_view	Change string_view::at to make it work with gcc and VC++. Thanks to K-ballo for the bug report, and Jonathan Wakeley for the code review in the bar.	2015-02-23 21:12:02 +00:00
system_error	Define a new macro: _LIBCPP_HAS_NO_VARIABLE_TEMPLATES and use it. No functionality change.	2015-03-17 15:30:22 +00:00
tuple	[libcxx] Add <experimental/tuple> header for LFTS.	2015-03-17 18:28:14 +00:00
type_traits	Define a new macro: _LIBCPP_HAS_NO_VARIABLE_TEMPLATES and use it. No functionality change.	2015-03-17 15:30:22 +00:00
utility	Add pragma system header to some experimental headers and add newlines to files.	2015-02-10 17:32:49 +00:00