clang/test/SemaCXX/cxx2a-nttp-printing.cpp

   1 // RUN: %clang_cc1 %s -std=c++20 -fsyntax-only -verify
   2
   3 template <int N> struct Str {
   4   constexpr Str(char const (&s)[N]) { __builtin_memcpy(value, s, N); }
   5   char value[N];
   6 };
   7
   8 template <Str V> class ASCII {};
   9
  10 void Foo(ASCII<"this nontype template argument is too long to print">); // expected-note {{no known conversion from 'ASCII<Str<43>{"this nontype template argument is too long"}>' to 'ASCII<Str<52>{"this nontype template argument is too long to print"}>'}}
  11 void Bar(ASCII<"this nttp argument is too short">);                     // expected-note {{no known conversion from 'ASCII<Str<14>{{119, 97, 105, 116, 32, 97, 32, 115, 27, 99, 111, 110, 100, 0}}>' to 'ASCII<Str<32>{"this nttp argument is too short"}>'}}
  12 void Meow(ASCII<"what|">);                                              // expected-note {{no known conversion from 'ASCII<Str<8>{"what??!"}>' to 'ASCII<Str<6>{"what|"}>' for 1st argument}}
  13
  14 void test_ascii() {
  15   ASCII<"this nontype template argument"
  16         " is too long">
  17       a;
  18   Foo(a);                 // expected-error {{no matching function}}
  19   decltype(a)::display(); // expected-error {{no member named 'display' in 'ASCII<Str<43>{"this nontype template argument is [...]"}>'}}
  20 }
  21
  22 void test_non_ascii() {
  23   ASCII<"wait a s\033cond"> a;
  24   Bar(a);                 // expected-error {{no matching function}}
  25   decltype(a)::display(); // expected-error {{no member named 'display' in 'ASCII<Str<14>{{119, 97, 105, 116, 32, 97, 32, 115, 27, 99, ...}}>'}}
  26 }
  27
  28 // The dialects (C++20 and above) that accept string literals as non-type
  29 // template arguments do not support trigraphs.
  30 void test_trigraph() {
  31   ASCII<"what??!"> a;     // expected-warning {{trigraph ignored}}
  32   Meow(a);                // expected-error {{no matching function}}
  33   decltype(a)::display(); // expected-error {{no member named 'display' in 'ASCII<Str<8>{"what??!"}>'}}
  34 }