A Tasty Treats Podcast for Web Developers.

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Wes Bos

Wes Bos

Full Stack JavaScript Developer. Creator of really good web development courses. BBQ enthusiast.

Scott Tolinski

Scott Tolinski

Web Developer, Creator of Level Up Tuts, Bboy, Robotops Crew and Youtuber

Playing: 377: Hasty Treat - TypeScript Utility Types

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LOUDNESS

Aug 9th, 2021

Hasty Treat - TypeScript Utility Types

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In this Hasty Treat, Scott and Wes talk about TypeScript utility types — what they are, why you might use them, why they exist, and more!

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Show Notes

03:35 - Levels of using TypeScript

  1. Typing your code
  2. Typing your code, but getting a little bit more dynamic using utility types
  3. Creating your own utility types!
  4. TypeScript is a language in itself
  5. Check out type challenges if you want your mind blown: https://github.com/type-challenges/type-challenges/
  6. https://www.typescriptlang.org/docs/handbook/utility-types.html

07:29 - Partial

08:23 - ReadOnly

09:00 - Required

09:33 - Record

  • A record is an object type that is a bit more restrictive
  • Say you want to store podcast details - name, URL, showCount, etc., but only for Syntax and Shoptalk.

10:47 - Omit

  • I find this one handy when I want to create a "Create Item" type, where it has all the item fields except the ID field

11:34 - Pick

  • Given a type, pick these properties

12:39 - Return Types

  • Gives you the type that is returned from a function. Handy if you need to dynamically generate the type based on a passed function.

13:30 - Case

  • These case types are useful for when you are doing template literal types
  • Uppercase<StringType>
  • Lowercase<StringType>
  • Capitalize<StringType>
  • Uncapitalize<StringType>

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