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// Test that `variant_count` only gets evaluated once the type is concrete enough.
#![feature(variant_count)]
pub struct GetVariantCount<T>(T);
impl<T> GetVariantCount<T> {
pub const VALUE: usize = std::mem::variant_count::<T>();
}
const fn check_variant_count<T>() -> bool {
matches!(GetVariantCount::<T>::VALUE, GetVariantCount::<T>::VALUE)
//~^ ERROR constant pattern depends on a generic parameter
}
fn main() {
assert!(check_variant_count::<Option<()>>());
}
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