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What happens when trying to convert an object to a number.
Some JavaScript values are not JSON safe
NaN, Not a Number, is returned when doing math operations with values that aren't numbers.
Using a value in a comparison can be confusing sometimes because JavaScript tries to be helpful and implicitly change the type for you.
Filtering an array with another array is useful when you have many elements you want to remove from an array.
In JavaScript functions can be declared with function statements, anonymous functions and arrow functions.
when creating a property on a object that has the same property name on its prototype it will shadow it.
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localStorage allows you to store and access strings in your browser.
The Fibonacci Sequence is a series of numbers that starts at 0 and 1. The next number in the series is the sum of the last two numbers.
Factorial can be used to find out how many ways to order a set of things. it looks like this 7!.
Semantic HTML are HTML tags that tell you what type of information each element should contain.
Well-organized code can be easier to debug, and easier to revisit later. Let's make sure we understand how to organize our code using the best practices.
Destructuring assignment is a special JavaScript syntax that makes it possible to assign multiple variables to elements of an array or properties of an object. It is very useful when you are trying to assign multiple variables or get values of an array and/or object.
Labels are great for describing what a input is for. Learn how and why to use labels.
There's a principle in programming called DRY, or Don't Repeat Yourself. It usually means refactoring code by taking something done several times and turning it into a loop or a function
Unlike other data types you might have seen so far, it is not possible to correctly compare two arrays by using the === or == comparison operator. Two primitive data type values can be equal, but no two arrays are the same, even if they have the same elements inside.
CSS treats each HTML element as if it is in its own box. This box will either be a block-level box or an inline box. It has the following positioning types that allow you to control the layout of a page normal flow, relative positioning, and absolute positioning.
The rest operator actually uses the same syntax as the spread operator. It's usage determines whether you're using it as the spread or rest operator.
Styling your site to look different depending on the size of a screen it is being viewed on is known as responsive web design.
When requests to a web sever come in you have this process called authentication that lets the server figure out exactly who made that request.
Keeping track of every single HTML element might become difficult. There's this CSS naming convention called block element modifier, also known as BEM. What it means is there are three different CSS classes of tags.
Sometimes when installing software, it might not give you an option to set an environment variable. Learn how to set environment variables in windows 10
Numbers, strings, booleans, undefined, null are 5 out of the 6 primitives, or basic data types. The other one is symbol, which represents an identifier for object properties.
To understand why let and const were added, it’s probably best to look at an example of when using var can get tricky.
Objects are containers that encapsulate data - meaning all of the relevant data and functions for the thing that the variable name represents are kept together in a 'capsule', better known as an object that can be created and manipulated in our programs as a single unit.
A closure is when a function can access its scope even if the function is executed outside of it.
Each element on a web page takes up space, and the box model describes the space around the element.
When you are writing HTML (or any other programming language), well-written code follows consistent indentation and spacing patterns.
In this blog I'll introduce the concept of responsive images, images that work well on devices with widely differing screen sizes, and resolutions, and how to implement them on the web using the picture element and srcset attribute.
git commit --amend is an easy way to modify the most recent commit, but if we need to modify history going further back then we'll need to use the git rebase -i command.
We always want to include clear and detailed messages with our commits. However, even the most careful developers can make mistakes. Git has several options to re-write git history, including a git commit.
HTML Block elements are elements that when displayed start on a line of their own, in effect making a block on the page. Inline elements do not appear on their own line but share a line with other inline elements.
Classes are great for selectively applying styles to certain parts of your web pages. But sometimes you'll have entire sections of your pages that you want to style a certain way, and adding a style to every tag gets annoying. Divs and spans can help.
JavaScript has the Spread Syntax that allows you to expand arrays or other iterable objects. It is very useful when you are trying to pass the elements of an array as single arguments to a function
Git is the tool that we can use to save all changes and additions to our code on the computer we're working on. GitHub is the online location we can upload our Git-managed code to for safekeeping.
Let's briefly note the difference between assigning a class to an HTML tag and assigning an id to an HTML tag.
behavior-driven devoplement (or BDD) is a process of taking a problem we want to solve or a concept we want to understand and turn it into a set of specific programming tasks.
Logical operators are used when doing comparisons of boolean values. if Booleans are being used it will either return true or false. If non-boolean values are used for operands if will return one of the specified operands. The logical operators look like (||), (&&) and (!).
In this blog, we're going to explore how JavaScript uses constructors as blueprints for the creation of many new objects, and prototypes for adding methods to objects.
find() finds an element in an array.
this refers to a object that is set is at the creation of a new execution context.
JavaScript is synchronous and single-threaded with capability to do asynchronous calls.
First class functions are functions that are treated like any other variable.
Primitives are immutable and passed by value. Objects are mutable and stored by reference.
Explanation of Git and 7 important Git commands.
You can think of a method as an action that a number, string or object can perform or have taken on it.
prototypical inheritance in JavaScript is an object with methods and properties that are given to non-primitive types.
floats and clear are important to know because you never know when you are going to be working on legacy code.
CSS introduces both pseudo-elements and pseudo-classes. A pseudo-element acts like an extra element is in the code. A pseudo-class acts like an extra value for a class attribute.
It's more fun to make web pages when we can show them off to our friends. There are a lot of ways to put our pages online, GitHub Pages is one way.
When we want to publish our code online (save it on the cloud so we can access it from any device), we want to store it in a remote repository.
map() allows you to make changes to every element in an array without modifying the original array.
reduce() method combines an array into one value
Now that we know how to setup Git, lets see how we can track changes.
filter() filters out elements in an array.
Git is a tool that we can use to save all changes and additions to our code on the computer we're working on.
an explanation of var, let, and const variable declarations in JavaScript.
explicación de const, let, y var declaración cuando usando JavaScript