Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/1uRsgp6. Jonathan Turner covers the challenges with growing and maintaining large JavaScript applications and how TypeScript addresses them. TypeScript is an open-source language developed by Microsoft built on web standards with a focus on early error detection and high quality tooling. Filmed at qconnewyork.com. Jonathan Turner is the program manager for the TypeScript team and a co-designer of the TypeScript language. Prior to joining Microsoft, he worked on Clang/LLVM and the Chapel programming language.

1. TYPESCRIPT: SCALING UP
JAVASCRIPT
Jonathan Turner – Program Manager, TypeScript

2. Watch the video with slide
synchronization on InfoQ.com!
http://www.infoq.com/presentations
/typescript-large-apps
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4. THIS TALK
What is TypeScript?
Basic features of TypeScript
Gradual conversion of JavaScript
Benefits of TypeScript
TypeScript community
Adoption of TypeScript

5. BACK IN THE DAY…

6. …TO TODAY

7. A LOOK AT JAVASCRIPT

8. A LOOK AT JAVASCRIPT: DYNAMIC TYPES

9. A LOOK AT JAVASCRIPT: CONSTRUCTORS

10. A LOOK AT JAVASCRIPT: IIFES

11. WHAT IS TYPESCRIPT?

12. TYPESCRIPT
All JavaScript code is TypeScript code, simply copy and paste
All JavaScript libraries work with TypeScript
Enable scalable application development and excellent tooling
Zero cost: Static types completely disappear at run-time
Compiles to idiomatic JavaScript
Runs in any browser or host, on any OS

14. BASIC FEATURES OF TYPESCRIPT
All JavaScript objects can be described with interfaces
Implicitly met based on shape
Allows using common OOP idioms
Compatible with future versions of JavaScript
Lightweight reusable code with no runtime overhead
Group related interfaces/classes/functions together
Move code out of the global namespace

16. TYPESCRIPT 1.0
Open Source, written in TypeScript.
Officially supported in Visual Studio and integrated into Visual Studio Online
via Monaco
Lots of samples, TypeScript handbook, language specification

17. TYPESCRIPT COMMUNITY
Over 6000 CodePlex posts, 200 forks, 2100 StackOverflow questions, 480 feature
requests
500+ .d.ts typings for a wide range of JavaScript libraries, including typings of DOM,
jQuery, node.js, WinRT, WinJS
ASP.NET, node.js, WebStorm, Eclipse, Sublime, grunt, Chutzpah
Used by Bing, Visual Studio, Monaco, Azure, Xbox, Adobe, Palantir, SitePen, eBay
Classifieds Group, and more

18. CONCLUSION

19. QUESTIONS?

20. Watch the video with slide synchronization on
InfoQ.com!
http://www.infoq.com/presentations/typescript
-large-apps