Struct std::any::TypeId

pub struct TypeId { /* fields omitted */ }

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.

Methods

impl TypeId

fn of<T>() -> TypeId where T: 'static + ?Sized

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>()
}

fn main() {
    assert_eq!(is_string(&0), false);
    assert_eq!(is_string(&"cookie monster".to_string()), true);
}

Trait Implementations

impl Hash for TypeId

fn hash<__H>(&self, __arg_0: &mut __H) where __H: Hasher

Feeds this value into the state given, updating the hasher as necessary.

fn hash_slice<H>(data: &[Self], state: &mut H) where H: Hasher

Feeds a slice of this type into the state provided.

impl PartialEq<TypeId> for TypeId

fn eq(&self, __arg_0: &TypeId) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, __arg_0: &TypeId) -> bool

This method tests for !=.

impl Clone for TypeId

fn clone(&self) -> TypeId

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Eq for TypeId

impl Copy for TypeId

impl Debug for TypeId

fn fmt(&self, __arg_0: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.