Requirejs Interview Questions And Answers

requirejs interview questions and answers   Top 11 Requirejs Interview Questions And Answers

1) What is RequireJS?

RequireJS is a JavaScript library and file loader which manages the dependencies between JavaScript files and in modular programming. It also helps to improve the speed and quality of the code.

RequireJS was developed by David Mark. It is an open source library.


2) Why to use RequireJS?

● It is an open source JavaScript library under the MIT license.
● It provides asynchronous module loading.
● It has the ability to load nested dependencies.
● If you have many small files, then you don't need to worry about keeping track of dependencies order.
● It provides support for plugins and loads more than one JavaScript files.


3) What are the features of RequireJS?

Following are the features of RequireJS:

● It manages the dependencies between JavaScript files, improves the speed and quality of the code.
● It combines and minifies the modules into one script for an optimized experience.
● It reduces code complexity in large applications.
● It gathers different JavaScript files from different modules at the time of compilation.
● It allows for easy debugging as it loads the files from plain script tags.


4) What are the configuration options in RequireJS?

Following are the configuration options:

● baseUrl
● paths
● shim
● map
● config
● urlArgs
● waitSeconds
● packages
● context
● deps
● callback
● xhtml
● scriptType
● skipDataMain


5) What are RequireJS AMD modules?

A module in RequireJS is a scoped object and is not available in the global namespace. Hence, global namespace will not be polluted. RequireJS syntax allows to load modules faster without worrying about keeping track of the order of dependencies. You can load multiple versions of the same module in the same page.


6) How to define functions in RequireJS?

A module can also use a function for frameworks, without having dependencies. This can be done by using the following syntax:

define(function () {
   
   //Do setup work here
   return {
      state: ""karnataka"",
      city: ""bangalore""
   }
});


7) How to define functions with dependencies in RequireJS?

If the module is having dependencies, the placement of the first argument (array of dependency names), the second argument (defining function) and the return object that defines the module is shown in the following syntax:

define([""./mnc"", ""./startup""], 
   function(mnc, startup) {
        
      return {
         state: ""karnataka"",
         city: ""bangalore"",
      
         addCompany: function() {
            mnc.decrement(this);
            startup.add(this);
         }
      
      }
   }
);


8) How to define module as a function in RequireJS?

It is not mandatory for a module to return only objects, any valid value from a function can also be returned. The following syntax is used to define a module as a function:

define([""./mnc"", ""./startup""],
   function(mnc, startup) {
       
      return function(title) {
         return title ? (window.title = title) :
         startup.storeName + ' ' + mnc.name;
      }
      
   }
);


9) What do you mean by defining function in RequireJS?

The define() function can be used to load the modules (module can be an object, function, class or a code which is executed after loading a module). You can load different versions of the same module in the same page. The different versions can be analyzed in the same order, even if they are loaded in a different order:

define(['module1', 'module2'], function (module1, module2) {
   //define the module value by returning a value
   return function () {};
});


10) What are the characteristics of Optimizer in RequireJS?

The Optimizer in RequireJS has the following characteristics:

● .Combines script files together with the help of UglifyJS for default usage or Closure Compiler for Java usage.
● Combines CSS files together.


11) What are the usage of CDN resources in RequireJS?

The optimizer does not load scripts using the network resources/ CDN (Content Delivery Network). In case, the scripts need to be loaded using a CDN then you need to map these files to a module name and download the files to your local file path.