dart:js_interop library
A library for JS interop. Includes a JS type hierarchy to facilitate sound interop with JS. The JS type hierarchy is modeled after the actual type hierarchy in JS, and not the Dart type hierarchy.
Note: The JS types that are exposed through this library are currently wrapper types that are erased to their runtime types. The runtime types will differ based on the backend. In general, stick to using conversion functions that are exposed as extension methods e.g. 'toJS'.
WARNING: This library is still a work in progress. As such, JS types, allowed syntax, semantics, and functionality may all change, so avoid using this library in production.
Classes
Extensions
- BoolToJSBoolean
- ByteBufferToJSArrayBuffer
- ByteDataToJSDataView
- DoubleToJSNumber
- double -> JSNumber.
- Float32ListToJSFloat32Array
- Float64ListToJSFloat64Array
- FunctionToJSExportedDartFunction
- FutureOfJSAnyToJSPromise
- FutureOfVoidToJSPromise
- Int16ListToJSInt16Array
- Int32ListToJSInt32Array
- Int8ListToJSInt8Array
- JSArrayBufferToByteBuffer
- JSArrayBuffer <-> ByteBuffer
- JSArrayToList
- JSArray <-> List
- JSBooleanToBool
- JSBoolean <-> bool
- JSBoxedDartObjectToObject
- JSBoxedDartObject <-> Object
- JSDataViewToByteData
- JSDataView <-> ByteData
- JSExportedDartFunctionToFunction
- JSExportedDartFunction <-> Function
- JSFloat32ArrayToFloat32List
- JSFloat32Array <-> Float32List
- JSFloat64ArrayToFloat64List
- JSFloat64Array <-> Float64List
- JSFunctionUtilExtension
- Utility extensions for JSFunction.
- JSInt16ArrayToInt16List
- JSInt16Array <-> Int16List
- JSInt32ArrayToInt32List
- JSInt32Array <-> Int32List
- JSInt8ArrayToInt8List
- JSInt8Array <-> Int8List
- JSNumberToNumber
- JSNumber -> double or int.
- JSObjectUtilExtension
- Utility extensions for JSObject.
- JSPromiseToFuture
- JSPromise -> Future<JSAny?>.
- JSStringToString
- JSString <-> String
- JSUint16ArrayToInt16List
- JSUint16Array <-> Uint16List
- JSUint32ArrayToUint32List
- JSUint32Array <-> Uint32List
- JSUint8ArrayToUint8List
- JSUint8Array <-> Uint8List
- JSUint8ClampedArrayToUint8ClampedList
- JSUint8ClampedArray <-> Uint8ClampedList
- ListToJSArray
- NullableObjectUtilExtension
- Utility extensions for Object?.
- NullableUndefineableJSAnyExtension
-
JS
undefined
and JSnull
are internalized differently based on the backends. In the JS backends, Dartnull
can actually be JSundefined
or JSnull
. In dart2wasm, that's not the case: there's only one Wasm valuenull
can be. Therefore, when we get back JSnull
or JSundefined
, we internalize both as Dartnull
in dart2wasm, and when we pass Dartnull
to an interop API, we pass JSnull
. In the JS backends, Dartnull
retains its original value when passed back to an interop API. Be wary of writing code where this distinction betweennull
andundefined
matters. - NumToJSExtension
- num -> JSNumber.
- ObjectToJSBoxedDartObject
- StringToJSString
- Uint16ListToJSInt16Array
- Uint32ListToJSUint32Array
- Uint8ClampedListToJSUint8ClampedArray
- Uint8ListToJSUint8Array
Constants
- anonymous → const _Anonymous
-
An annotation that indicates a
JS
annotated class is structural and does not have a known JavaScript prototype._Anonymous()
- staticInterop → const _StaticInterop
-
staticInterop enables the
JS
annotated class to be treated as a "static" interop class._StaticInterop()
Properties
- globalContext → JSObject
-
A getter to retrieve the global context that is used in static interop
lowering.
no setter
Typedefs
- JSAny = JSAny
- The JS types users should use to write their external APIs.
- JSArray = JSArray
- The type of all JS arrays, JSArray <: JSObject.
- JSArrayBuffer = JSArrayBuffer
- The type of JS array buffers, JSArrayBuffer <: JSObject.
- JSBigInt = JSBigInt
- The type of JS BigInts, JSBigInt <: JSAny.
- JSBoolean = JSBoolean
- The type of JS booleans, JSBoolean <: JSAny.
- JSBoxedDartObject = JSBoxedDartObject
- The type of the boxed Dart object that can be passed to JS safely. There is no interface specified of this boxed object, and you may get a new box each time you box the same Dart object. JSBoxedDartObject <: JSObject.
- JSDataView = JSDataView
- The type of JS byte data, JSDataView <: JSObject.
- JSExportedDartFunction = JSExportedDartFunction
- The type of all Dart functions adapted to be callable from JS. We only allow a subset of Dart functions to be callable from JS, JSExportedDartFunction <: JSFunction.
- JSFloat32Array = JSFloat32Array
- JSFloat64Array = JSFloat64Array
- JSFunction = JSFunction
- The type of all JS functions, JSFunction <: JSObject.
- JSInt16Array = JSInt16Array
- JSInt32Array = JSInt32Array
- JSInt8Array = JSInt8Array
-
The typed arrays themselves,
*Array
<: JSTypedArray. - JSNumber = JSNumber
- The type of JS numbers, JSNumber <: JSAny.
- JSObject = JSObject
- The representation type of all JavaScript objects for inline classes, JSObject <: JSAny.
- JSPromise = JSPromise
- The type of JS promises and promise-like objects, JSPromise <: JSObject.
- JSString = JSString
- The type of JS strings, JSString <: JSAny.
- JSSymbol = JSSymbol
- The type of JS Symbols, JSSymbol <: JSAny.
- JSTypedArray = JSTypedArray
- The abstract supertype of all JS typed arrays, JSTypedArray <: JSObject.
- JSUint16Array = JSUint16Array
- JSUint32Array = JSUint32Array
- JSUint8Array = JSUint8Array
- JSUint8ClampedArray = JSUint8ClampedArray
- JSVoid = void
-
The type of
JSUndefined
when returned from functions. Unlike pure JS, no actual object will be returned.