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| // RUN: %clang_cc1 -std=c++1z %s -verify
namespace std {
template<typename> struct tuple_size;
template<int, typename> struct tuple_element;
}
struct Get {
template<int> int get() { return 0; }
operator bool() { return true; }
};
namespace std {
template<> struct tuple_size<Get> { static constexpr int value = 1; };
template<> struct tuple_element<0, Get> { using type = int; };
}
struct Na {
bool flag;
float data;
};
struct Rst {
bool flag;
float data;
explicit operator bool() const {
return flag;
}
};
Rst f();
Na g();
namespace CondInIf {
int h() {
if (auto [ok, d] = f()) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}}
;
if (auto [ok, d] = g()) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}} expected-error {{value of type 'Na' is not contextually convertible to 'bool'}}
;
if (auto [value] = Get()) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}}
return value;
}
} // namespace CondInIf
namespace CondInWhile {
int h() {
while (auto [ok, d] = f()) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}}
;
while (auto [ok, d] = g()) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}} expected-error {{value of type 'Na' is not contextually convertible to 'bool'}}
;
while (auto [value] = Get()) // expected-warning{{ISO C++17 does not permit structured binding declaration in a condition}}
return value;
}
} // namespace CondInWhile
namespace CondInFor {
int h() {
for (; auto [ok, d] = f();) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}}
;
for (; auto [ok, d] = g();) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}} expected-error {{value of type 'Na' is not contextually convertible to 'bool'}}
;
for (; auto [value] = Get();) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}}
return value;
}
} // namespace CondInFor
struct IntegerLike {
bool flag;
float data;
operator int() const {
return int(data);
}
};
namespace CondInSwitch {
int h(IntegerLike x) {
switch (auto [ok, d] = x) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}}
;
switch (auto [ok, d] = g()) // expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}} expected-error {{statement requires expression of integer type ('Na' invalid)}}
;
switch (auto [value] = Get()) {// expected-warning {{ISO C++17 does not permit structured binding declaration in a condition}}
// expected-warning@-1{{switch condition has boolean value}}
case 1:
return value;
}
}
} // namespace CondInSwitch
|