File: p3.cpp

package info (click to toggle)
llvm-toolchain-15 1%3A15.0.6-4
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 1,554,644 kB
  • sloc: cpp: 5,922,452; ansic: 1,012,136; asm: 674,362; python: 191,568; objc: 73,855; f90: 42,327; lisp: 31,913; pascal: 11,973; javascript: 10,144; sh: 9,421; perl: 7,447; ml: 5,527; awk: 3,523; makefile: 2,520; xml: 885; cs: 573; fortran: 567
file content (68 lines) | stat: -rw-r--r-- 3,024 bytes parent folder | download | duplicates (15)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
// RUN:  %clang_cc1 -std=c++2a -verify %s

template<typename T, typename U>
constexpr bool is_same_v = false;

template<typename T>
constexpr bool is_same_v<T, T> = true;

using T = void ();

void f1non_templ(int a) requires true; // expected-error{{non-templated function cannot have a requires clause}}
auto f2non_templ(int a) -> bool requires true; // expected-error{{non-templated function cannot have a requires clause}}
auto f3non_templ(int a) -> bool (*)(int b) requires true; // expected-error{{non-templated function cannot have a requires clause}}
// expected-error@+1{{non-templated function cannot have a requires clause}}
auto f4_non_templ(int a) requires true -> bool; // expected-error{{trailing return type must appear before trailing requires clause}}
void (f7non_templ()) requires true; // expected-error{{non-templated function cannot have a requires clause}}
// expected-error@+1{{non-templated function cannot have a requires clause}}
void (f8non_templ() requires true); // expected-error{{trailing requires clause should be placed outside parentheses}}
// expected-error@+1{{non-templated function cannot have a requires clause}}
T xnon_templ requires true;
// expected-error@+2 2{{non-templated function cannot have a requires clause}}
struct Snon_templ {
  T m1 requires true, m2 requires true;
};

template <typename>
void f1(int a)
  requires true;                               // OK

template <typename>
auto f2(int a) -> bool
  requires true;                                 // OK

template <typename>
auto f3(int a) -> bool (*)(int b) requires true; // OK
template <typename>
auto f4(int a) requires true -> bool; // expected-error{{trailing return type must appear before trailing requires clause}}
int f5(int a) requires; // expected-error{{expected expression}}
int f6(int a) requires {} // expected-error{{expected expression}}
template<typename>
void (f7()) requires true;
template<typename>
void (f8() requires true); // expected-error{{trailing requires clause should be placed outside parentheses}}
void (*(f9 requires (true)))(); // expected-error{{trailing requires clause should be placed outside parentheses}}
static_assert(is_same_v<decltype(f9), void (*)()>);
void (*pf)() requires true; // expected-error{{trailing requires clause can only be used when declaring a function}}
void g1(int (*dsdads)() requires false); // expected-error{{trailing requires clause can only be used when declaring a function}}
void g2(int (*(*dsdads)())() requires true); // expected-error{{trailing requires clause can only be used when declaring a function}}
void g3(int (*(*dsdads)(int) requires true)() ); // expected-error{{trailing requires clause should be placed outside parentheses}}

template<typename U>
struct Foo{
T x requires true;
};
Foo<int> f;

template<typename>
struct S {
  T m1 requires true, m2 requires true;
};

template<typename T>
struct R {
    R(T t);
};

template<typename T>
R(T) -> R<T> requires true; // expected-error{{deduction guide cannot have a requires clause}}