Discover advanced TypeScript concepts: Gain insights into compiler flags, generic types, and discriminated unions. Delve into writing error-free code and mastering complex error messages with confidence.

typescript-3.7.5.tar.gz

TypeScript 3.7.5 Strict

TypeScript 3.7.5

Are you using TypeScript, but feel like you’re not making the most out of it? Do you find some advanced TypeScript concepts confusing? Do you get lost looking at complex type errors?

If you answered “yes” to any of these questions, then this course is for you! It introduces you to the world of advanced TypeScript concepts including: compiler flags for catching more errors, generic types, and how to compose types with discriminated unions. 

After finishing this course, you’ll feel more confident in your TypeScript skills. You will be able to write types that detect whole classes of possible runtime errors at compile time. Typing even the most untypeable JavaScript code will be a no brainer for you, and you’ll be fluent in TypeScript error messages.

Advanced TypeScript Masterclass

# Overview

TypeScript lets you define your own type guards. A custom type guard is a Boolean-returning function that can additionally assert something about the type of its parameter. If the function is called in the context of a conditional expression, the type of the passed value is narrowed to the asserted type inside the positive branch of the conditional.

Below, you can see an example of an `isArticle` type guard. It's a function that takes an object and checks if it's an instance of `Article` by checking for the presence of certain properties. Later, when the function is used inside the `if` statement, the type of `body` is narrowed to `Article` in the first branch of the conditional statement.

This lesson explains custom type guards and how they're useful.

Strict types

Generics

Composing types

Advanced types

TypeScript in practice

Conclusion

Custom Type Guards

Overview