[PATCH] D145642: [clang-format] Annotate lambdas with requires clauses.

[Owen Pan via Phabricator via cfe-commits]

owenpan added a comment.

In D145642#4186462 <https://reviews.llvm.org/D145642#4186462>, @rymiel wrote:

> Could you please clarify what you mean by "regressions" here? Isn't the behaviour of this syntax broken to begin with? It doesn't change anything about lambdas without //requires-clause//s

Let's use you example <https://godbolt.org/z/x8oT5Y9bz>:

  $ cat test.cpp
  #include <type_traits>
  
  template <typename T>
  struct foo {
      static const bool value = true;
  };
  
  template <typename T>
  inline constexpr bool foo_v = foo<T>::value;
  
  template <typename T>
  concept foo_c = foo_v<T>;
  
  int main() {
    [&]<typename Callable>
      requires foo<Callable>::value
    (Callable&& callable)
    {
      static_cast<void>(callable);
    };
  
    [&]<typename Callable>
      requires foo_c<Callable>
    (Callable&& callable)
    {
      static_cast<void>(callable);
    };
  
    [&]<typename Callable>
      requires foo_v<Callable>
    (Callable&& callable)
    {
      static_cast<void>(callable);
    };
  }
  $ clang-format -version
  clang-format version 17.0.0 (https://github.com/llvm/llvm-project f6e7a5c29221f445e4cbddc32667a1e12a1446db)
  $ clang-format test.cpp
  #include <type_traits>
  
  template <typename T> struct foo {
    static const bool value = true;
  };
  
  template <typename T> inline constexpr bool foo_v = foo<T>::value;
  
  template <typename T>
  concept foo_c = foo_v<T>;
  
  int main() {
    [&]<typename Callable>
      requires foo<Callable>::value(Callable && callable)
    {
      static_cast<void>(callable);
    };
  
    [&]<typename Callable>
      requires foo_c<Callable>(Callable && callable)
    {
      static_cast<void>(callable);
    };
  
    [&]<typename Callable>
      requires foo_v<Callable>(Callable && callable)
    {
      static_cast<void>(callable);
    };
  }

If this patch would merge the lambda bodies into single lines, would that be considered a possible regression? My guess is that it would be unless the lambda bodies should be merged in the first place, in which case the patch would also fix a formatting bug in addition to the annotation bug.


Repository:
  rG LLVM Github Monorepo

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https://reviews.llvm.org/D145642