Trait TidExt 

pub trait TidExt<'a>: Tid<'a> {
    // Provided methods
    fn is<T>(&self) -> bool
       where T: Tid<'a> { ... }
    fn downcast_ref<'b, T>(&'b self) -> Option<&'b T>
       where T: Tid<'a> { ... }
    fn downcast_mut<'b, T>(&'b mut self) -> Option<&'b mut T>
       where T: Tid<'a> { ... }
    fn downcast_rc<T>(self: Rc<Self>) -> Result<Rc<T>, Rc<Self>>
       where T: Tid<'a> { ... }
    fn downcast_arc<T>(self: Arc<Self>) -> Result<Arc<T>, Arc<Self>>
       where T: Tid<'a> { ... }
    fn downcast_box<T>(self: Box<Self>) -> Result<Box<T>, Box<Self>>
       where T: Tid<'a> { ... }
    fn downcast_move<T>(self) -> Option<T>
       where T: Tid<'a>,
             Self: Sized { ... }
}

Re-export public API. Extension trait that contains actual downcasting methods.

Use methods from this trait only if dyn Tid was created directly from T for this particular T

If Self is Sized then any of those calls is optimized to no-op because both T and Self are known statically. Useful if you have generic code that you want to behave differently depending on which concrete type replaces type parameter. Usually there are better ways to do this like specialization, but sometimes it can be the only way.

Provided Methods

fn is<T>(&self) -> bool

where T: Tid<'a>,

Returns true if type behind self is equal to the type of T.

fn downcast_ref<'b, T>(&'b self) -> Option<&'b T>

where T: Tid<'a>,

Attempts to downcast self to T behind reference

fn downcast_mut<'b, T>(&'b mut self) -> Option<&'b mut T>

where T: Tid<'a>,

Attempts to downcast self to T behind mutable reference

fn downcast_rc<T>(self: Rc<Self>) -> Result<Rc<T>, Rc<Self>>

where T: Tid<'a>,

Attempts to downcast self to T behind Rc pointer

fn downcast_arc<T>(self: Arc<Self>) -> Result<Arc<T>, Arc<Self>>

where T: Tid<'a>,

Attempts to downcast self to T behind Arc pointer

fn downcast_box<T>(self: Box<Self>) -> Result<Box<T>, Box<Self>>

where T: Tid<'a>,

Attempts to downcast self to T behind Box pointer

fn downcast_move<T>(self) -> Option<T>

where T: Tid<'a>, Self: Sized,

Attempts to downcast owned Self to T, useful only in generic context as a workaround for specialization

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<'a, X> TidExt<'a> for X

where X: Tid<'a> + ?Sized,