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

## Explicit `any` annotation

The simplest way to fix errors caused by enabling `noImplicitAny` is simply explicitly marking the type as `any`. How is this better than skipping the type annotation altogether? It's still unsafe, right? 

Correct; but with explicit annotations, it's much easier to spot these occurrences (for example, during code reviews). Because of the propagating aspect of `any`, it's easy to not realize that some portion of code is not type-checked. Making `any` explicit addresses this issue.

# Explicit `any` annotation

The simplest way to fix errors caused by enabling `noImplicitAny` is simply explicitly marking the type as `any`. How is this better than skipping the type annotation altogether? It's still unsafe, right? 

Correct; but with explicit annotations, it's much easier to spot these occurrences (for example, during code reviews). Because of the propagating aspect of `any`, it's easy to not realize that some portion of code is not type-checked. Making `any` explicit addresses this issue.

This lesson discusses techniques of addressing compilation errors caused by enabling `noImplicitAny`.

Strict types

Generics

Composing types

Advanced types

TypeScript in practice

Conclusion

Fixing `noImplicitAny` Errors

Explicit `any` annotation