kauress
Break and continue statements The break statement is used to exit a loop completely once a condition has been met, or after x number of iterations. As such it is commonly used within an if conditional block. Take as an example the following code: for (let i = 0; i <= 5; i++){ console.log(i); } This will print out the value of variable i from
Copying objects with deep copy The JSON.stringify and JSON.parse methods can be used to deep copy an object. In a deep copy, the source and target objects have different memory addresses and are not connected at all. The JSON.stringify() method will take a JavaScript object as an argument and transform it into a string. Then the JSON.parse() method will parse the JavaScript string and return
Copying objects with Shallow copy Now that we went over shallow and deep copies in part 1, let’s go over shallow copying in JavaScript. There are 3 ways to create shallow copies in JavaScript: Iteration using for key in an object Spread operator Object.assign() 1. Iteration using for key in an object In order to copy the items of an object into another object we
Copying objects with shallow and deep copies Primitive values such as strings, and numbers are copied by value, whereas objects are copied by reference. What do we mean by this? The following code example will explain this practically: let num1 = 10; let num2 = num1; num1 = 6; console.log(num2); //10 The value of num1 which is the number 10 is assigned to the variable
Pass by value Non-primitive data types are passed by reference compared to primitive data types that are passed by value. As such non-primitive data types are also called reference types. To understand why they’re called reference types, we need to briefly look at how variables are stored in memory. A fixed amount of memory is allocated to a variable after it is declared. For primitive
Introduction Execution context is an abstract concept describing the environment within which JavaScript code is executed. The execution context will dictate if a variable, object, or another block of code is accessible or not. There are two types of execution contexts: global and function. Let’s examine the global execution context first. Global execution context The global execution context is the default execution context. Variables and
Introduction JavaScript is single-threaded this means that the main thread on which code is executed runs one line at a time. There is no possibility of doing anything in parallel. Therefore, the run time is blocked until a task is completed. An example of blocking the run time is an infinite loop. However, the DOM API, setTimeout() , setInterval() methods are provided by the web
What is the call stack? An understanding of the call stack will allow you to understand how execution order in JavaScript works. JavaScript is a single-threaded language; this means that it handles one task at a time. JavaScript code is executed by the JavaScript engine. Google’s V8 engine is an example of a popular JavaScript engine, there are others such as the SpiderMonkey and Rhino.
Pre-Launch It’s been a busy 2 days, I pre-launched the JavaScript Technical Interview Guide and have sold 50% of the early bird copies. I made an announcement on Twitter and on Reddit. So far 280 upvotes on Reddit! Anyways keep reading – the juice is down below! So far I’ve emailed subscribers once with 80 practice coding exercises from chapter 1 (The Basics) . Besides
Introduction Hi devs especially junior devs! For the past 5 months I’ve been super focused on writing a technical interview guide for juniors who want to break into the web-development industry. Since a solid grounding in JavaScript is paramount to clearing interviews focused on web applications, I wanted to write a guide that would help junior developers learn and practice at the same time. Why?
