What are type assertions in TypeScript?

What are type assertions in TypeScript?

Type assertions in TypeScript allow you to override the inferred type of a variable. It's a way to tell the compiler, 'Trust me, I know what I'm doing.'

Can you give me an example of how to use type assertions?

Sure! For instance, if you have a variable let someValue: any = 'this is a string';, you can assert its type like this: let strLength: number = (someValue as string).length;.

Are there different ways to assert types?

Yes, you can use either the as syntax or the angle-bracket syntax. For example: let strLength: number = (<string>someValue).length;.

When should I use type assertions?

Use type assertions when you have more information about the type than TypeScript can infer, but be cautious as it can lead to runtime errors if used incorrectly.