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//@ build-pass
// issue 122301 - currently the only way to supress
// const eval and codegen of code conditional on some other const
struct Foo<T, const N: usize>(T);
impl<T, const N: usize> Foo<T, N> {
const BAR: () = if N == 0 {
panic!()
};
}
struct Invoke<T, const N: usize>(T);
impl<T, const N: usize> Invoke<T, N> {
const FUN: fn() = if N != 0 {
|| Foo::<T, N>::BAR
} else {
|| {}
};
}
// without closures
struct S<T>(T);
impl<T> S<T> {
const C: () = panic!();
}
const fn bar<T>() { S::<T>::C }
struct ConstIf<T, const N: usize>(T);
impl<T, const N: usize> ConstIf<T, N> {
const VAL: () = if N != 0 {
bar::<T>() // not called for N == 0, and hence not monomorphized
} else {
()
};
}
fn main() {
let _val = Invoke::<(), 0>::FUN();
let _val = ConstIf::<(), 0>::VAL;
}
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