What does 2 exclamation mark mean in typescript?

The 2 exclamation mark is used to show that the value is required or mandatory within the function or class. This is usually used to make sure the argument is provided before running the function or class. Use the two exclamation marks when you want to make sure the function or class doesn’t run if the argument is missing.

What does exclamation marks mean in JS?

Sometimes you will see the exclamation mark in JavaScript code without having any surrounding punctuation marks. This is because the code is not just text – it is an instruction for your code to perform a certain action. When you encounter the exclamation mark alone in a line of code, it is usually denoting an event handler.

What does two exclamation marks mean in HTML?

If you notice while looking at some source code, you will see two exclamation marks after the opening tag in the HTML. If you are using the Web Developer or Chrome Developer Tools, you can see that the two characters are not actually part of the code and show up to alert the developer that something is wrong with the code. The two exclamation marks are called validation tokens.

What does exclamation mark mean in Javascript?

An exclamation mark is often used as a punctuation mark in JavaScript. It is used to call a function or to indicate an error. You can use the parenthesis or the comma to call a function. An error is shown to you when the code you enter is not valid. The interpreter will stop and show you the line number and the error.

What does "exclamation marks mean in HTML?

For example, is written with two question marks. This tag indicates the start and end of an image. An example of an empty attribute can be . The src="" tells the browser where to find the image.