Titanium Mobile # util.types
util.types provides type checks for different kinds of built-in objects. Unlike instanceof or Object.prototype.toString.call(value), these checks do not inspect properties of the object that are accessible from JavaScript (like their prototype), and usually have the overhead of calling into C++.
The result generally does not make any guarantees about what kinds of properties or behavior a value exposes in JavaScript. They are primarily useful for addon developers who prefer to do type checking in JavaScript.
8.1.0
8.1.0
9.2.0NOTE
This is an abstract type. Any object of this structure can be used where this type is used.
# Methods
# isAnyArrayBuffer
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in ArrayBuffer or SharedArrayBuffer instance.
See also util.types.isArrayBuffer() and util.types.isSharedArrayBuffer().
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isArgumentsObject
8.1.0 8.1.0 9.2.0Returns true if the value is an arguments object.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isArrayBuffer
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in ArrayBuffer instance. This does not include SharedArrayBuffer instances. Usually, it is desirable to test for both; See util.types.isAnyArrayBuffer() for that.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isArrayBufferView
8.1.0 8.1.0 9.2.0Returns true if the value is an instance of one of the ArrayBuffer views, such as typed array objects or DataView. Equivalent to ArrayBuffer.isView().
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isAsyncFunction
8.1.0 8.1.0 9.2.0Returns true if the value is an async function. This only reports back what the JavaScript engine is seeing; in particular, the return value may not match the original source code if a transpilation tool was used.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isBigInt64Array
8.1.0 8.1.0 9.2.0Returns true if the value is a Bigint64Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isBigUint64Array
8.1.0 8.1.0 9.2.0Returns true if the value is a BigUint64Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isBooleanObject
8.1.0 8.1.0 9.2.0Returns true if the value is a boolean object, e.g. created by new Boolean().
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isBoxedPrimitive
8.1.0 8.1.0 9.2.0Returns true if the value is any boxed primitive object, e.g. created by new Boolean(), new String() or Object(Symbol()).
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isDataView
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in DataView instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isDate
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Date instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isFloat32Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Float32Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isFloat64Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Float64Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isGeneratorFunction
8.1.0 8.1.0 9.2.0Returns true if the value is a generator function. This only reports back what the JavaScript engine is seeing; in particular, the return value may not match the original source code if a transpilation tool was used.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isGeneratorObject
8.1.0 8.1.0 9.2.0Returns true if the value is a generator object as returned from a built-in generator function. This only reports back what the JavaScript engine is seeing; in particular, the return value may not match the original source code if a transpilation tool was used.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isInt16Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Int16Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isInt32Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Int32Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isInt8Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Int8Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isMap
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Map instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isMapIterator
8.1.0 8.1.0 9.2.0Returns true if the value is an iterator returned for a built-in Map instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isNativeError
8.1.0 8.1.0 9.2.0Returns true if the value is an instance of a built-in Error type.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isNumberObject
8.1.0 8.1.0 9.2.0Returns true if the value is a number object, e.g. created by new Number().
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isPromise
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Promise.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isRegExp
8.1.0 8.1.0 9.2.0Returns true if the value is a regular expression object.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isSet
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Set instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isSetIterator
8.1.0 8.1.0 9.2.0Returns true if the value is an iterator returned for a built-in Set instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isSharedArrayBuffer
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in SharedArrayBuffer instance. This does not include ArrayBuffer instances. Usually, it is desirable to test for both; See util.types.isAnyArrayBuffer() for that.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isStringObject
8.1.0 8.1.0 9.2.0Returns true if the value is a string object, e.g. created by new String().
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isSymbolObject
8.1.0 8.1.0 9.2.0Returns true if the value is a symbol object, created by calling Object() on a Symbol primitive.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isTypedArray
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in TypedArray instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isUint16Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Uint16Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isUint32Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Uint32Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isUint8Array
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Uint8Array instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isUint8ClampedArray
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in Uint8ClampedArray instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isWeakMap
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in WeakMap instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean
# isWeakSet
8.1.0 8.1.0 9.2.0Returns true if the value is a built-in WeakSet instance.
Parameters
| Name | Type | Description |
|---|---|---|
value | any | value to check |
Returns
- Type
- Boolean