gi-gobject-2.0.21: GObject bindings

Copyright Will Thompson Iñaki García Etxebarria and Jonas Platte LGPL-2.1 Iñaki García Etxebarria (inaki@blueleaf.cc) None Haskell2010

GI.GObject.Structs.WeakRef

Contents

Description

A structure containing a weak reference to a Object. It can either be empty (i.e. point to Nothing), or point to an object for as long as at least one "strong" reference to that object exists. Before the object's ObjectClass.dispose method is called, every WeakRef associated with becomes empty (i.e. points to Nothing).

Like Value, WeakRef can be statically allocated, stack- or heap-allocated, or embedded in larger structures.

Unlike g_object_weak_ref() and g_object_add_weak_pointer(), this weak reference is thread-safe: converting a weak pointer to a reference is atomic with respect to invalidation of weak pointers to destroyed objects.

If the object's ObjectClass.dispose method results in additional references to the object being held, any GWeakRefs taken before it was disposed will continue to point to Nothing. If GWeakRefs are taken after the object is disposed and re-referenced, they will continue to point to it until its refcount goes back to zero, at which point they too will be invalidated.

Synopsis

Exported types

newtype WeakRef Source #

Memory-managed wrapper type.

Constructors

 WeakRef (ManagedPtr WeakRef)
Instances
 Source # Instance detailsDefined in GI.GObject.Structs.WeakRef Methods

A convenience alias for Nothing :: Maybe WeakRef.