[libcxx-commits] [PATCH] D142843: [libc++] Addresses LWG3358

[Louis Dionne via Phabricator via libcxx-commits]

ldionne added inline comments.


================
Comment at: libcxx/test/std/containers/views/views.span/span.cons/iterator_sentinel.pass.cpp:123
+  std::array a{42};
+  TEST_VALIDATE_EXCEPTION((std::span<int>{throw_operator_minus{a.begin()}, throw_operator_minus{a.end()}}),    //
+                          int,                                                                                 //
----------------
philnik wrote:
> Mordante wrote:
> > philnik wrote:
> > > Why not just a try/catch like we normally do?
> > I added new macros to make this simpler in D142808, this is based on the macros in rapid-cxx-test.h which we have, but they seem quite unknown.
> TBH I don't think this is a readability improvement. This just makes it harder to see what's going on.
Yeah, I must agree that seeing it in use here it isn't super easy to read. This would be the equivalent code right?


```
try {
  std::span<int> s{throw_operator_minus{a.begin()}, throw_operator_minus{a.end()}});
  assert(false);
} catch (int i) {
  assert(i == 42);
}
```

I think the part that gets confusing here is probably the fact that we have a predicate that tests the content of the exception. I wonder how useful that is in practice. Otherwise, this could look like `TEST_THROWS(int, []{ statements... })`, which IMO is easy to read.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D142843/new/

https://reviews.llvm.org/D142843