std::any::TypeId - Rust
Description: API documentation for the Rust `TypeId` struct in crate `std`.
Keywords: rust, rustlang, rust-lang, TypeId

# Struct std::any::TypeId 1.0.0 [−] [src]

    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.

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 outside of your code!

## Methods

### `impl TypeId`
[src]

#### `pub fn of<T>() -> TypeId where
T: 'static + ?Sized,`
[src]

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);
    }Run

## Trait Implementations

### `impl Clone for TypeId`
[src]

#### `fn clone(&self) -> TypeId`
[src]

Returns a copy of the value. Read more

#### `fn clone_from(&mut self, source: &Self)`
[src]

Performs copy-assignment from `source`. Read more

### `impl PartialOrd<TypeId> for TypeId`
[src]

#### `fn partial_cmp(&self, __arg_0: &TypeId) -> Option<Ordering>`
[src]

This method returns an ordering between `self` and `other` values if one exists. Read more

#### `fn lt(&self, __arg_0: &TypeId) -> bool`
[src]

This method tests less than (for `self` and `other`) and is used by the `<` operator. Read more

#### `fn le(&self, __arg_0: &TypeId) -> bool`
[src]

This method tests less than or equal to (for `self` and `other`) and is used by the `<=` operator. Read more

#### `fn gt(&self, __arg_0: &TypeId) -> bool`
[src]

This method tests greater than (for `self` and `other`) and is used by the `>` operator. Read more

#### `fn ge(&self, __arg_0: &TypeId) -> bool`
[src]

This method tests greater than or equal to (for `self` and `other`) and is used by the `>=` operator. Read more

### `impl Eq for TypeId`
[src]

### `impl Copy for TypeId`
[src]

### `impl Ord for TypeId`
[src]

#### `fn cmp(&self, __arg_0: &TypeId) -> Ordering`
[src]

This method returns an `Ordering` between `self` and `other`. Read more

#### `fn max(self, other: Self) -> Self`
1.21.0
[src]

Compares and returns the maximum of two values. Read more

#### `fn min(self, other: Self) -> Self`
1.21.0
[src]

Compares and returns the minimum of two values. Read more

### `impl PartialEq<TypeId> for TypeId`
[src]

#### `fn eq(&self, __arg_0: &TypeId) -> bool`
[src]

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

#### `fn ne(&self, __arg_0: &TypeId) -> bool`
[src]

This method tests for `!=`.

### `impl Debug for TypeId`
[src]

#### `fn fmt(&self, __arg_0: &mut Formatter) -> Result<(), Error>`
[src]

Formats the value using the given formatter. Read more

### `impl Hash for TypeId`
[src]

#### `fn hash<__H>(&self, __arg_0: &mut __H) where
__H: Hasher,`
[src]

Feeds this value into the given [`Hasher`]. Read more

#### `fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,`
1.3.0
[src]

Feeds a slice of this type into the given [`Hasher`]. Read more

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