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
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);Trait Implementations
This method returns an ordering between self and other values if one exists. Read more
This method tests less than (for self and other) and is used by the < operator. Read more
This method tests less than or equal to (for self and other) and is used by the <=
operator. Read more
This method tests greater than (for self and other) and is used by the > operator. Read more
Auto Trait Implementations
impl RefUnwindSafe for TypeId
impl UnwindSafe for TypeId
Blanket Implementations
Mutably borrows from an owned value. Read more
Causes self to use its Binary implementation when Debug-formatted.
Causes self to use its Display implementation when
Debug-formatted. Read more
Causes self to use its LowerExp implementation when
Debug-formatted. Read more
Causes self to use its LowerHex implementation when
Debug-formatted. Read more
Causes self to use its Octal implementation when Debug-formatted.
Causes self to use its Pointer implementation when
Debug-formatted. Read more
Causes self to use its UpperExp implementation when
Debug-formatted. Read more
Causes self to use its UpperHex implementation when
Debug-formatted. Read more
Pipes by value. This is generally the method you want to use. Read more
Borrows self and passes that borrow into the pipe function. Read more
Mutably borrows self and passes that borrow into the pipe function. Read more
Borrows self, then passes self.borrow() into the pipe function. Read more
Mutably borrows self, then passes self.borrow_mut() into the pipe
function. Read more
Borrows self, then passes self.as_ref() into the pipe function.
Mutably borrows self, then passes self.as_mut() into the pipe
function. Read more
Borrows self, then passes self.deref() into the pipe function.
fn pipe_as_ref<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: AsRef<T>,
T: 'a,
R: 'a,
fn pipe_as_ref<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: AsRef<T>,
T: 'a,
R: 'a,
Pipes a trait borrow into a function that cannot normally be called in suffix position. Read more
fn pipe_borrow<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: Borrow<T>,
T: 'a,
R: 'a,
fn pipe_borrow<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: Borrow<T>,
T: 'a,
R: 'a,
Pipes a trait borrow into a function that cannot normally be called in suffix position. Read more
fn pipe_deref<'a, R>(&'a self, func: impl FnOnce(&'a Self::Target) -> R) -> R where
Self: Deref,
R: 'a,
fn pipe_deref<'a, R>(&'a self, func: impl FnOnce(&'a Self::Target) -> R) -> R where
Self: Deref,
R: 'a,
Pipes a dereference into a function that cannot normally be called in suffix position. Read more
Pipes a reference into a function that cannot ordinarily be called in suffix position. Read more
Immutable access to the Borrow<B> of a value. Read more
Mutable access to the BorrowMut<B> of a value. Read more
Immutable access to the AsRef<R> view of a value. Read more
Mutable access to the AsMut<R> view of a value. Read more
Immutable access to the Deref::Target of a value. Read more
Mutable access to the Deref::Target of a value. Read more
Calls .tap() only in debug builds, and is erased in release builds.
Calls .tap_mut() only in debug builds, and is erased in release
builds. Read more
Calls .tap_borrow() only in debug builds, and is erased in release
builds. Read more
Calls .tap_borrow_mut() only in debug builds, and is erased in release
builds. Read more
Calls .tap_ref() only in debug builds, and is erased in release
builds. Read more
Calls .tap_ref_mut() only in debug builds, and is erased in release
builds. Read more
Calls .tap_deref() only in debug builds, and is erased in release
builds. Read more
Provides immutable access to the reference for inspection.
Calls tap_ref in debug builds, and does nothing in release builds.
Provides mutable access to the reference for modification.
Calls tap_ref_mut in debug builds, and does nothing in release builds.
Provides immutable access to the borrow for inspection. Read more
Calls tap_borrow in debug builds, and does nothing in release builds.
fn tap_borrow_mut<F, R>(self, func: F) -> Self where
Self: BorrowMut<T>,
F: FnOnce(&mut T) -> R,
fn tap_borrow_mut<F, R>(self, func: F) -> Self where
Self: BorrowMut<T>,
F: FnOnce(&mut T) -> R,
Provides mutable access to the borrow for modification.
Immutably dereferences self for inspection.
fn tap_deref_dbg<F, R>(self, func: F) -> Self where
Self: Deref,
F: FnOnce(&Self::Target) -> R,
fn tap_deref_dbg<F, R>(self, func: F) -> Self where
Self: Deref,
F: FnOnce(&Self::Target) -> R,
Calls tap_deref in debug builds, and does nothing in release builds.
fn tap_deref_mut<F, R>(self, func: F) -> Self where
Self: DerefMut,
F: FnOnce(&mut Self::Target) -> R,
fn tap_deref_mut<F, R>(self, func: F) -> Self where
Self: DerefMut,
F: FnOnce(&mut Self::Target) -> R,
Mutably dereferences self for modification.