Commonly you see the Uncaught TypeError: cannot set property innerText of null error if you try to access an HTML element on a page before it appears. The solution. Move your JavaScript from the head to the body tag below the HTML element you are trying to access. An Example Situation Let’s say you are […]
Uncaught TypeError: cannot set property ‘innerHTML’ of null Read More »
To ask for user input in JavaScript, use the built-in window.prompt() method. For example: This shows the following modal at the top of your page: Prompt Box in JavaScript To ask for user input in JavaScript, you can use the built-in prompt box. To show a prompt, use the prompt() method. This method takes two
JavaScript How to Ask User for Input (A Complete Guide) Read More »
The difference between undefined and undeclared variables in JavaScript is: This is a comprehensive guide to understanding the differences between undefined and undeclared in JavaScript. Examples The best way to understand the difference between undefined and undeclared in JavaScript is by having a look at examples. Example 1: Undefined Variable To see an example of
Undefined vs Undeclared in JavaScript Read More »
In JavaScript, there are three types of popup boxes: Here is the syntax for using each of them: This is a complete guide to popups in JavaScript. You will learn how and why to use the three different popup types in JavaScript. The guide shows you simple and illustrative examples. JavaScript Popup Modals Here is
JavaScript Popup Boxes Read More »
To remove spaces from a string in Python, use the str.replace() method. This method takes two arguments: For example: Output: This is the quick answer. To learn other useful string methods in Python, feel free to check this article. In this guide, we take a look at other common situations related to removing spaces from
How to Remove Spaces from String in Python Read More »
The __qualname__ attribute means qualified name in Python. It gives you a dotted path to the name of the target object. Using __qualname__ is useful with nested structures, such as when you have a method inside a class. For example: The result of this is a full path to the attribute: __qualname__ vs __name__ in
What Is __qualname__ in Python Read More »
To use a while loop to find the factorial of a number in Python: Here is how it looks in code: Let’s test that it works: Output: There you have it! To learn more about factorials and some alternative ways to calculate the factorial, please read along. What Is the Factorial of a Number in
Factorial with a While Loop in Python Read More »
In Python, a metaclass is a “class of a class”. It defines how a class itself is constructed. Whenever you create a Python class, a metaclass is invoked under the hood. This metaclass turns the class into a Python object. To truly understand what a metaclass is, you need to understand how classes work. In
What Are Metaclasses in Python Read More »
The difference between the yield and the return statement in Python is: I’m sure this raises more questions than it answers. Let’s go through yield in Python in great detail. Our goal is to understand why and when should one use yield over the return statement in Python. Generators in Python Any function that yields
Yield vs Return in Python Read More »
In Python, self refers to the class object itself. With self, you are able to access the attributes and methods of the class. For instance, this Fruit class assigns a custom name and color to itself upon creation. These can then be accessed by the info() method: Output: To understand how this works, let’s dive
What Is ‘self’ in Python? A Complete Guide (with Examples) Read More »
