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As seen above, a promise encapsulates the result of an asynchronous operation. You can use anyhow you want a promise: return from a function, use as an argument, assign to variables. That's the first benefit. The second big benefit is that promises can create chains to handle multiple depe...
The NaN is a property that is rarely used in any program because it is not a good practice to use NaN to identify anything in the program. There is a global isNaN() method to accomplish this task, which returns true if the argument passed to it is not a number. Otherwise, it will...
When you invoke a function in JavaScript, a new execution context is created and added to the call stack. The execution context contains athisreference or athisbinding that will be used throughout the function’s execution. Whatthisreferences is entirely determined by the call site (the location...
There are lots of different type conversions described in the spec. One of them isToInteger. JavaScript uses it when a standard function expects an integer argument. Before the use of the passed argument, JavaScript appliesToIntegerto the value of that argument. If the value is NaN, thenToIn...
greet('World') is the regular function invocation. The function greet('World') accepts data from the argument.Before I go on, let me recommend something to you because I know that the path to becoming a professional JavaScript developer isn't easy... I recommend certificates.dev’s ...
A callback function in JavaScript is a function that is passed as an argument to another function and is invoked after some kind of event.
For the last several years, JavaScript has been evolving on a steady cadence with new language features. If you’re curious to see what’s in store for the next version of JavaScript, this post is for you! Before we talk about the latest features, it’s important to understand how new ...
A polyfill basically is a browser fallback piece of code which makes the modern browser based functionality available in older browsers too. This means that HTML5 and CSS3 functionality like “placeholder“, “Canvas”, “video”, “transform” etc can be used even on an old browser. So whi...
Parallelism in JavaScript is an exciting concept that enables true concurrent execution of tasks, even in a primarily single-threaded language. With the introduction of Web Workers, you can tap into the power of parallelism and achieve significant performance improvements in your JavaScript applications...