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Optional Function Arguments in JavaScript

The call method calls a function with a given this value and arguments provided individually. While the syntax of this function is almost identical to that of applythe fundamental difference is that call accepts an argument listwhile apply accepts a single array of arguments.

The result of calling the function with the specified this value and arguments. With callyou can write a method once and then inherit it in another object, without having to rewrite the method for the new object. You can use call to chain constructors for an object, similar to Java.

Named arguments in JavaScript

In the following example, the constructor for the Product object is defined with two parameters, name and price. Two other functions Food and Toy invoke Product passing this and name and price. Product initializes the how to make a good counterfeit money name and priceboth specialized functions define the category.

In this purely constructed example, we create an anonymous function and use call to invoke it on every object in an array. The main purpose of the anonymous function javascript call function with named arguments is to add a print function to every object, which is able to print the right index of the object in the array.

Javascript call function with named arguments the object as this value was not strictly necessary, but is done for explanatory purpose. Introduction to Object-Oriented JavaScript. Get the latest and greatest from MDN delivered straight to your inbox.

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Using named arguments in JavaScript functions

Get Firefox help Get web development help Join the MDN community Report a content problem Report a bug. In This Article Syntax Parameters Return value Description Examples Using call to chain constructors for an object Using call to invoke an anonymous function Using call to invoke a function and specifying the context for 'this' Specifications Browser compatibility See also.

Feature Chrome Edge Firefox Gecko Internet Explorer Opera Safari Basic support Yes Yes Yes Yes Yes Yes. Feature Android Chrome for Android Edge Firefox Mobile Gecko IE Mobile Opera Mobile Safari Mobile Basic support Yes Yes Yes Yes Yes Yes Yes.

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Please check your inbox to confirm your subscription. About MDN Terms Privacy Cookies Contribute to the code. ECMAScript 1st Edition ECMA ECMAScript 6th Edition, ECMA The definition of 'Function. ECMAScript Latest Draft ECMA The definition of 'Function.