#[repr(transparent)]pub struct Exception(_);
Expand description
An Objective-C exception.
While highly recommended that any exceptions you intend to throw are
subclasses of NSException
, this is not required by the runtime (similar
to how Rust can panic with arbitary payloads using panic_any
).
Methods from Deref<Target = Object>§
sourcepub unsafe fn ivar_ptr<T: Encode>(&self, name: &str) -> *mut T
pub unsafe fn ivar_ptr<T: Encode>(&self, name: &str) -> *mut T
Returns a pointer to the instance variable / ivar with the given name.
This is similar to UnsafeCell::get
, see that for more information
on what is and isn’t safe to do.
Usually you will have defined the instance variable yourself with
ClassBuilder::add_ivar
, the type of the ivar T
must match the
type used in that.
Attempting to access or modify private implementation details of a class that you do no control using this is not supported, and may invoke undefined behaviour.
Library implementors are strongly encouraged to expose a safe interface to the ivar.
Panics
May panic if the object has no ivar with the given name. May also
panic if the type encoding of the ivar differs from the type encoding
of T
.
This should purely seen as help while debugging and is not guaranteed
(e.g. it may be disabled when debug_assertions
are off).
Safety
The object must have an instance variable with the given name, and it
must be of type T
. Any invariants that the object have assumed about
the value of the instance variable must not be violated.
No thread syncronization is done on accesses to the variable, so you must ensure that any access to the returned pointer do not cause data races, and that Rust’s mutability rules are not otherwise violated.
sourcepub unsafe fn ivar<T: Encode>(&self, name: &str) -> &T
pub unsafe fn ivar<T: Encode>(&self, name: &str) -> &T
Returns a reference to the instance variable with the given name.
See Object::ivar_ptr
for more information, including on when this
panics.
Safety
The object must have an instance variable with the given name, and it
must be of type T
.
No thread syncronization is done, so you must ensure that no other
thread is concurrently mutating the variable. This requirement can be
considered upheld if all mutation happens through Object::ivar_mut
(since that takes &mut self
).