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// This test is from #73976. We previously did not check if a type is monomorphized
// before calculating its type id, which leads to the bizarre behaviour below that
// TypeId of a generic type does not match itself.
//
// This test case should either run-pass or be rejected at compile time.
// Currently we just disallow this usage and require pattern is monomorphic.
#![feature(const_type_id)]
#![feature(const_type_name)]
use std::any::{self, TypeId};
pub struct GetTypeId<T>(T);
impl<T: 'static> GetTypeId<T> {
pub const VALUE: TypeId = TypeId::of::<T>();
}
const fn check_type_id<T: 'static>() -> bool {
matches!(GetTypeId::<T>::VALUE, GetTypeId::<T>::VALUE)
//~^ ERROR constant pattern cannot depend on generic parameters
}
pub struct GetTypeNameLen<T>(T);
impl<T: 'static> GetTypeNameLen<T> {
pub const VALUE: usize = any::type_name::<T>().len();
}
const fn check_type_name_len<T: 'static>() -> bool {
matches!(GetTypeNameLen::<T>::VALUE, GetTypeNameLen::<T>::VALUE)
//~^ ERROR constant pattern cannot depend on generic parameters
}
fn main() {
assert!(check_type_id::<usize>());
assert!(check_type_name_len::<usize>());
}
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