clang/test/Parser/cxx2b-lambdas.cpp

   1 // RUN: %clang_cc1 -std=c++2b %s -verify
   2
   3 auto LL0 = [] {};
   4 auto LL1 = []() {};
   5 auto LL2 = []() mutable {};
   6 auto LL3 = []() constexpr {};
   7
   8 auto L0 = [] constexpr {};
   9 auto L1 = [] mutable {};
  10 auto L2 = [] noexcept {};
  11 auto L3 = [] constexpr mutable {};
  12 auto L4 = [] mutable constexpr {};
  13 auto L5 = [] constexpr mutable noexcept {};
  14 auto L6 = [s = 1] mutable {};
  15 auto L7 = [s = 1] constexpr mutable noexcept {};
  16 auto L8 = [] -> bool { return true; };
  17 auto L9 = []<typename T> { return true; };
  18 auto L10 = []<typename T> noexcept { return true; };
  19 auto L11 = []<typename T> -> bool { return true; };
  20 auto L12 = [] consteval {};
  21 auto L13 = []() requires true {};
  22 auto L14 = []<auto> requires true() requires true {};
  23 auto L15 = []<auto> requires true noexcept {};
  24 auto L16 = [] [[maybe_unused]]{};
  25
  26 auto XL0 = [] mutable constexpr mutable {};    // expected-error{{cannot appear multiple times}}
  27 auto XL1 = [] constexpr mutable constexpr {};  // expected-error{{cannot appear multiple times}}
  28 auto XL2 = []) constexpr mutable constexpr {}; // expected-error{{expected body of lambda expression}}
  29 auto XL3 = []( constexpr mutable constexpr {}; // expected-error{{invalid storage class specifier}} \
  30                                                // expected-error{{function parameter cannot be constexpr}} \
  31                                                // expected-error{{a type specifier is required}} \
  32                                                // expected-error{{expected ')'}} \
  33                                                // expected-note{{to match this '('}} \
  34                                                // expected-error{{expected body}} \
  35                                                // expected-warning{{duplicate 'constexpr'}}
  36
  37 // http://llvm.org/PR49736
  38 auto XL4 = [] requires true {}; // expected-error{{expected body}}
  39 auto XL5 = []<auto> requires true requires true {}; // expected-error{{expected body}}
  40 auto XL6 = []<auto> requires true noexcept requires true {}; // expected-error{{expected body}}
  41
  42 auto XL7 = []() static static {}; // expected-error {{cannot appear multiple times}}
  43 auto XL8 = []() static mutable {}; // expected-error {{cannot be both mutable and static}}
  44 auto XL9 = []() static consteval {};
  45 auto XL10 = []() static constexpr {};
  46
  47 auto XL11 = [] static {};
  48 auto XL12 = []() static {};
  49 auto XL13 = []() static extern {};  // expected-error {{expected body of lambda expression}}
  50 auto XL14 = []() extern {};  // expected-error {{expected body of lambda expression}}
  51
  52
  53 void static_captures() {
  54   int x;
  55   auto SC1 = [&]() static {}; // expected-error {{a static lambda cannot have any captures}}
  56   auto SC4 = [x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  57   auto SC2 = [&x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  58   auto SC3 = [y=x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  59   auto SC5 = [&y = x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  60   auto SC6 = [=]() static {}; // expected-error {{a static lambda cannot have any captures}}
  61   struct X {
  62     int z;
  63     void f() {
  64       [this]() static {}(); // expected-error {{a static lambda cannot have any captures}}
  65       [*this]() static {}(); // expected-error {{a static lambda cannot have any captures}}
  66     }
  67   };
  68 }