GI.JavaScriptCore.Objects.WeakValue

JSCWeakValue represents a weak reference to a value in a Context. It can be used to keep a reference to a JavaScript value without protecting it from being garbage collected and without referencing the Context either.

Exported types

newtype WeakValue

Memory-managed wrapper type.

Constructors

WeakValue (ManagedPtr WeakValue)

Instances

Eq WeakValue

Defined in GI.JavaScriptCore.Objects.WeakValue

Methods

(==) :: WeakValue -> WeakValue -> Bool

(/=) :: WeakValue -> WeakValue -> Bool

GObject WeakValue

Defined in GI.JavaScriptCore.Objects.WeakValue

ManagedPtrNewtype WeakValue

Defined in GI.JavaScriptCore.Objects.WeakValue

Methods

toManagedPtr :: WeakValue -> ManagedPtr WeakValue

TypedObject WeakValue

Defined in GI.JavaScriptCore.Objects.WeakValue

Methods

glibType :: IO GType

HasParentTypes WeakValue

Defined in GI.JavaScriptCore.Objects.WeakValue

IsGValue (Maybe WeakValue)

Convert WeakValue to and from GValue. See toGValue and fromGValue.

Defined in GI.JavaScriptCore.Objects.WeakValue

Methods

gvalueGType_ :: IO GType

gvalueSet_ :: Ptr GValue -> Maybe WeakValue -> IO ()

gvalueGet_ :: Ptr GValue -> IO (Maybe WeakValue)

type ParentTypes WeakValue

Defined in GI.JavaScriptCore.Objects.WeakValue

type ParentTypes WeakValue = '[Object]

class (GObject o, IsDescendantOf WeakValue o) => IsWeakValue o

Type class for types which can be safely cast to WeakValue, for instance with toWeakValue.

Instances

(GObject o, IsDescendantOf WeakValue o) => IsWeakValue o

Defined in GI.JavaScriptCore.Objects.WeakValue

toWeakValue :: (MonadIO m, IsWeakValue o) => o -> m WeakValue

Cast to WeakValue, for types for which this is known to be safe. For general casts, use castTo.

Methods

Click to display all available methods, including inherited ones

Methods

bindProperty, bindPropertyFull, forceFloating, freezeNotify, getv, isFloating, notify, notifyByPspec, ref, refSink, runDispose, stealData, stealQdata, thawNotify, unref, watchClosure.

Getters

getData, getProperty, getQdata, getValue.

Setters

setData, setDataFull, setProperty.

getValue

weakValueGetValue

Arguments

:: (HasCallStack, MonadIO m, IsWeakValue a)

=> a

weakValue: a WeakValue

-> m Value

Returns: a new Value or Nothing if weakValue was cleared.

Get a Value referencing the JavaScript value of weakValue.

new

weakValueNew

Arguments

:: (HasCallStack, MonadIO m, IsValue a)

=> a

value: a Value

-> m WeakValue

Returns: a new WeakValue

Create a new WeakValue for the JavaScript value referenced by value.

Properties

value

The Value referencing the JavaScript value.

constructWeakValueValue :: (IsWeakValue o, MonadIO m, IsValue a) => a -> m (GValueConstruct o)

Construct a GValueConstruct with valid value for the “value” property. This is rarely needed directly, but it is used by new.

Signals

cleared

type WeakValueClearedCallback = IO ()

This signal is emitted when the JavaScript value is destroyed.

afterWeakValueCleared :: (IsWeakValue a, MonadIO m) => a -> ((?self :: a) => WeakValueClearedCallback) -> m SignalHandlerId

Connect a signal handler for the cleared signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after weakValue #cleared callback

By default the object invoking the signal is not passed to the callback. If you need to access it, you can use the implit ?self parameter. Note that this requires activating the ImplicitParams GHC extension.

onWeakValueCleared :: (IsWeakValue a, MonadIO m) => a -> ((?self :: a) => WeakValueClearedCallback) -> m SignalHandlerId

Connect a signal handler for the cleared signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on weakValue #cleared callback