Struct objc2::declare::IvarDrop

pub struct IvarDrop<T> { /* private fields */ }

A helper type to allow putting certain types that may drop into ivars.

This is used to work around current limitations in the type system. Consider this type “temporary” in the sense that one day it may just become type IvarDrop<T> = T.

This currently works with the following types:

• Box<T>
• Option<Box<T>>
• Id<T, O>
• Option<Id<T, O>>

Further may be added when the standard library guarantees their layout.

See examples/delegate.rs for usage.

Trait Implementations

impl<T: Sized> InnerIvarType for IvarDrop<Box<T>>

type Output = Box<T, Global>

The type that an Ivar containing this will dereference to.

impl<T: Message, O: Ownership> InnerIvarType for IvarDrop<Id<T, O>>

type Output = Id<T, O>

The type that an Ivar containing this will dereference to.

impl<T: Sized> InnerIvarType for IvarDrop<Option<Box<T>>>

type Output = Option<Box<T, Global>>

The type that an Ivar containing this will dereference to.

impl<T: Message, O: Ownership> InnerIvarType for IvarDrop<Option<Id<T, O>>>

type Output = Option<Id<T, O>>

The type that an Ivar containing this will dereference to.