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// Modified example from P2582R1
// { dg-do compile { target c++23 } }
template <typename T> struct B {
B(T);
};
B(bool) -> B<char>;
template <typename T> struct C : public B<T> {
using B<T>::B;
};
template <typename T> struct D : public B<T> {};
C c(42); // OK, deduces C<int>
using ty1 = decltype(c);
using ty1 = C<int>;
D d(42); // { dg-error "deduction|no match" }
C c2(true); // OK, deduces C<char>
using ty2 = decltype(c2);
using ty2 = C<char>;
template <typename T> struct E : public B<int> {
using B<int>::B;
};
E e(42); // { dg-error "deduction|no match" }
template <typename T, typename U, typename V> struct F {
F(T, U, V);
};
template <typename T, typename U> struct G : F<U, T, int> {
using F<U, T, int>::F;
};
G g(true, 'a', 1); // OK, deduces G<char, bool>
using ty3 = decltype(g);
using ty3 = G<char, bool>;
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