Struct wayland_server::UserDataMap [−][src]
pub struct UserDataMap { /* fields omitted */ }
Expand description
A storage able to store several values of UserData
of different types. It behaves similarly to a TypeMap
.
Implementations
Create a new map
Attempt to access the wrapped user data of a given type
Will return None
if no value of type T
is stored in this UserDataMap
and accessible from this thread
Insert a value in the map if it is not already there
This is the non-threadsafe variant, the type you insert don’t have to be threadsafe, but they will not be visible from other threads (even if they are actually threadsafe).
If the value does not already exists, the closure is called to create it and
this function returns true
. If the value already exists, the closure is not
called, and this function returns false
.
Insert a value in the map if it is not already there
This is the threadsafe variant, the type you insert must be threadsafe and will be visible from all threads.
If the value does not already exists, the closure is called to create it and
this function returns true
. If the value already exists, the closure is not
called, and this function returns false
.
Trait Implementations
Returns the “default value” for a type. Read more
Auto Trait Implementations
impl RefUnwindSafe for UserDataMap
impl Send for UserDataMap
impl Sync for UserDataMap
impl Unpin for UserDataMap
impl !UnwindSafe for UserDataMap
Blanket Implementations
Mutably borrows from an owned value. Read more
Convert Box<dyn Trait>
(where Trait: Downcast
) to Box<dyn Any>
. Box<dyn Any>
can
then be further downcast
into Box<ConcreteType>
where ConcreteType
implements Trait
. Read more
Convert Rc<Trait>
(where Trait: Downcast
) to Rc<Any>
. Rc<Any>
can then be
further downcast
into Rc<ConcreteType>
where ConcreteType
implements Trait
. Read more
Convert &Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &Any
’s vtable from &Trait
’s. Read more
Convert &mut Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &mut Any
’s vtable from &mut Trait
’s. Read more