What does double exclamation mark mean in typescript?

The double exclamation mark is often used in JavaScript to indicate that a method is immediately invoked. It can also be used to indicate a default value.

What does exclamation point mean in typescript?

The exclamation point is used in JavaScript to indicate an alert or an assertion. You can use the exclamation point in JavaScript to alert the developer of something that is not expected to happen. For example, if you were creating a simple calculator, you might want to alert the user if a number is entered that isn’t an integer. You could use an alert to tell the user that the number they entered is not an integer.

What does!! mean in typescript?

The two exclamation marks are used in JavaScript to alert the developer that something is wrong. Consider the following example:

What does exclamation mark mean in JSON?

It’s sometimes used in JavaScript Object Notation (JSON) to indicate that the value is a boolean. It’s not the only way to declare boolean values in JSON — you can also use the true and false keywords. The exclamation mark is used to show that the value is true.

What does two exclamation marks mean in typescript?

The exclamation mark is used in JavaScript as an alert call. Because it is used as a character in JavaScript, another way of writing the alert call is writing a question mark inside two single quotes. For example alert('Hello!'); will alert Hello! The alert call also takes two optional arguments. The first is the title of the alert. The second argument is the message that will be displayed within the alert box.