[libcxx-commits] [PATCH] D149706: [libc++][PSTL] Implement std::copy{, _n}

[Nikolas Klauser via Phabricator via libcxx-commits]

philnik added inline comments.


================
Comment at: libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/pstl.copy.pass.cpp:98
+int main(int, char**) {
+  types::for_each(types::forward_iterator_list<int*>{}, TestIteratorsInt{});
+  types::for_each(types::forward_iterator_list<CopiedToTester*>{}, TestIteratorsNonTrivial{});
----------------
ldionne wrote:
> I see this is repeating a lot, and because of C++17 we can't use template lambas. But we can do this:
> 
> ```
> types::for_each(types::forward_iterator_list<int*>{}, types::apply_type_identity([](auto It) {
>   using Iter = typename decltype(It)::type;
>   // the rest of your stuff
> }));
> 
> // where
> template <class F>
> struct apply_type_identity {
>   F f;
>   template <class ...Args>
>   auto operator()() const {
>     return f(std::type_identity<Args>{}...);
>   }
> };
> ```
> 
> We can bikeshed about the name of `apply_type_identity`, I'm open to anything reasonable. IMO if we apply this throughout, it will localize the "loops" and make the testing code easier to read (and write!). WDYT?
I'm not a huge fan of the name, but I can't come up with anything better.


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https://reviews.llvm.org/D149706