pub struct TypeId { /* private fields */ }
Expand description
A TypeId
represents a globally unique identifier for a type.
Each TypeId
is an opaque object which does not allow inspection of what’s
inside but does allow basic operations such as cloning, comparison,
printing, and showing.
A TypeId
is currently only available for types which ascribe to 'static
,
but this limitation may be removed in the future.
While TypeId
implements Hash
, PartialOrd
, and Ord
, it is worth
noting that the hashes and ordering will vary between Rust releases. Beware
of relying on them inside of your code!
Implementations§
source§impl TypeId
impl TypeId
const: unstable · sourcepub fn of<T: ?Sized + 'static>() -> TypeId
pub fn of<T: ?Sized + 'static>() -> TypeId
Returns the TypeId
of the type this generic function has been
instantiated with.
Examples
use std::any::{Any, TypeId};
fn is_string<T: ?Sized + Any>(_s: &T) -> bool {
TypeId::of::<String>() == TypeId::of::<T>()
}
assert_eq!(is_string(&0), false);
assert_eq!(is_string(&"cookie monster".to_string()), true);
Run