[JS] callback function

https://www.dashingd3js.com/lessons/javascript-callback-functions

JavaScript Callback Functions | DashingD3js.com

 

• A JavaScript function is a block of code that will be executed when you call it
• Because JavaScript functions are first-class objects, you can pass functions to other functions as variables
• The method of passing in functions as parameters to other functions to use them inside is used in JavaScript libraries almost everywhere
• A JavaScript Callback Function is a function that is passed as a parameter to another JavaScript function, and the callback function is run inside of the function it was passed into
• JavaScript Callback Functions can be used synchronously or asynchronously

 

 

This method of passing in functions to other functions to use them inside is used in JavaScript libraries almost everywhere.

The common name for the function passed in is a callback function.

In computer programming, a callback is a piece of executable code that is passed as an argument to other code, which is expected to call back (execute) the argument at some convenient time.

The invocation may be immediate as in a synchronous callback or it might happen at later time, as in an asynchronous callback.