About stdlib...
We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.
The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.
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Test whether a value has in its prototype chain a specified constructor as a prototype property.
npm install @stdlib/assert-instance-of
Alternatively,
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var instanceOf = require( '@stdlib/assert-instance-of' );
Tests whether a value has in its prototype chain a specified constructor as a prototype property.
var inherit = require( '@stdlib/utils-inherit' ); function Foo() { return this; } function Bar() { return this; } inherit( Bar, Foo ); var bar = new Bar(); var bool = instanceOf( bar, Foo ); // returns true
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The function throws a
TypeErrorif provided aconstructorargument which is not callable.var bool = instanceOf( {}, null ); // throws <TypeError>
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While the prototype of an
objectcreated using object literal notion isundefined, the function returnstruewhen provided anobjectliteral and theObjectconstructor. This maintains consistent behavior with theinstanceofoperator.var Object = require( '@stdlib/object-ctor' ); var bool = ( {} instanceof Object ); // returns true bool = instanceOf( {}, Object ); // returns true
var Number = require( '@stdlib/number-ctor' ); var Object = require( '@stdlib/object-ctor' ); var Function = require( '@stdlib/function-ctor' ); var instanceOf = require( '@stdlib/assert-instance-of' ); var bool = instanceOf( [], Array ); // returns true bool = instanceOf( [], Object ); // returns true bool = instanceOf( {}, Object ); // returns true bool = instanceOf( new Date(), Date ); // returns true bool = instanceOf( /.*/, RegExp ); // returns true bool = instanceOf( instanceOf, Function ); // returns true bool = instanceOf( null, Object ); // returns false bool = instanceOf( 5, Number ); // returns false bool = instanceOf( '5', String ); // returns false bool = instanceOf( void 0, Object ); // returns false bool = instanceOf( {}, Array ); // returns false bool = instanceOf( {}, Function ); // returns false
@stdlib/assert-is-prototype-of: test if an object's prototype chain contains a provided prototype.@stdlib/utils-constructor-name: determine the name of a value's constructor.@stdlib/utils-inherit: implement prototypical inheritance by replacing the prototype of one constructor with the prototype of another constructor.@stdlib/utils-type-of: determine a value's type.
This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.
See LICENSE.
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