Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
A Non-Zero Number of TypeScript Tips
Search
Toby Ho
August 20, 2018
Programming
0
720
A Non-Zero Number of TypeScript Tips
An introduction to TypeScript.
Toby Ho
August 20, 2018
Tweet
Share
More Decks by Toby Ho
See All by Toby Ho
Debugging Ajax Calls
airportyh
0
110
How to Learn 3
airportyh
2
82
How to Learn 2
airportyh
0
98
How To Learn
airportyh
7
1.4k
Test-Driven Development that Feels Great
airportyh
0
8.8k
Other Decks in Programming
See All in Programming
猫と暮らすネットワークカメラ生活🐈 ~Vision frameworkでペットを愛でよう~ / iOSDC Japan 2025
yutailang0119
0
220
overlayPreferenceValue で実現する ピュア SwiftUI な AdMob ネイティブ広告
uhucream
0
110
高度なUI/UXこそHotwireで作ろう Kaigi on Rails 2025
naofumi
4
3.5k
いま中途半端なSwift 6対応をするより、Default ActorやApproachable Concurrencyを有効にしてからでいいんじゃない?
yimajo
2
340
CSC509 Lecture 06
javiergs
PRO
0
240
CSC305 Lecture 01
javiergs
PRO
1
400
タスクの特性や不確実性に応じた最適な作業スタイルの選択(ペアプロ・モブプロ・ソロプロ)と実践 / Optimal Work Style Selection: Pair, Mob, or Solo Programming.
honyanya
3
140
Introducing ReActionView: A new ActionView-Compatible ERB Engine @ Kaigi on Rails 2025, Tokyo, Japan
marcoroth
3
920
CSC509 Lecture 05
javiergs
PRO
0
290
Swift Concurrency - 状態監視の罠
objectiveaudio
2
450
Catch Up: Go Style Guide Update
andpad
0
170
Your Perfect Project Setup for Angular @BASTA! 2025 in Mainz
manfredsteyer
PRO
0
130
Featured
See All Featured
Fantastic passwords and where to find them - at NoRuKo
philnash
52
3.4k
Music & Morning Musume
bryan
46
6.8k
"I'm Feeling Lucky" - Building Great Search Experiences for Today's Users (#IAC19)
danielanewman
229
22k
Measuring & Analyzing Core Web Vitals
bluesmoon
9
610
Understanding Cognitive Biases in Performance Measurement
bluesmoon
29
2.6k
Building Adaptive Systems
keathley
43
2.8k
XXLCSS - How to scale CSS and keep your sanity
sugarenia
248
1.3M
Save Time (by Creating Custom Rails Generators)
garrettdimon
PRO
32
1.6k
VelocityConf: Rendering Performance Case Studies
addyosmani
332
24k
Producing Creativity
orderedlist
PRO
347
40k
Creating an realtime collaboration tool: Agile Flush - .NET Oxford
marcduiker
32
2.2k
Facilitating Awesome Meetings
lara
56
6.6k
Transcript
A non-zero number of TypeScript Tips
Agenda • What and why • Interfaces • Optional Properties
• Class • Generic functions / methods • Strict Null Checks • VS Code Shortcuts
What is TypeScript?
What is TypeScript • Super set of JavaScript / EcmaScript
• EcmaScript Future Proof
Why TypeScript?
Type Definitions
Interfaces the shape of an object
Interface
Interface
Interface
Interface
Implementing an Interface with a Class
Class Constructor Shorthand Equivalent shorthand to previous slide
Interface Extension
Optional Properties
None
None
Optional Properties This property is optional
Type assertion (or casting)
Type assertion (or casting) Don’t do this!!!
TypeScript Static type checking with loopholes.
Interface with Methods
Implementing an Interface with Methods
Generic Functions
Put a number in a list
Put a string in a list
Generic a thing in a list
Generic Function/Methods
Generic Function/Methods TypeScript knows!!!
Generic Types
Parameterized Types (generics) T is a type parameter
Parameterized Types
Parameterized Type: Promises
Promises Uses the fetch API
Promises
Promises Uses the fetch API
Generic Function with Generic Type!!!
Generic getItems
Generic getItems But what is articles? What is T?
Generic getItems
Generic getItems Define T explicitly
Generic getItems Or define related type and let TS infer
what T is
Generic getItems T is inferred to be IArticle based on
this related type declaration
Generic getItems
Strict Null Checks
Strict Null Checks This property is optional
Strict Null Checks tsconfig.json
Strict Null Checks
Strict Null Checks
Strict Null Checks
VS Code Help
VSCode Auto Import Helper
VSCode Auto Import Helper Click that!!!
VSCode Auto Import Helper
VSCode: Looking up type definitions Mac: Command+click Windows: Control+click Mac:
Command+hover Windows: Control+hover Popup: Drilldown:
Popup
Drilldown
Summary • What and why • Interfaces • Optional Properties
• Class • Generic functions / methods • Strict Null Checks • VS Code Shortcuts