typescript - your regular javascript on steroids

#FullStackCon 2015

“Everything that can be written in JavaScript, will eventually be written in JavaScript”

Atwood’s Law

JavaScript was originally developed for applications with a

few hundred lines of code! “Netscape”, 1995

HelloI’m Christos

christosmatskas cmatskas https://cmatskas.com

Enterprise Projects

Mobile applications

Side Projects

Javascript won the war.

Enterprise-Scale

• Refactoring• Building components• Static typing• Go to definition, renaming etc

Ratified in 2015 Long overdue Missing features Slow browser adoption

EcmaScript2015 (ES6)

Slow adoption

Compilers & Polyfils

• Babel• Traceur• TypeScript

TypeScript: A language for large scale

JavaScript development.

TypeScript: A typed superset of JavaScript that

compiles to plain JavaScript.

Any browser. Any host. Any OS.

Open SourceURL: https://

github.com/Microsoft/TypeScript

+ +

+ +

Structural typing and type inference In practice very few type annotations are

necessary

Generics Increases accuracy and expressiveness of

type system

Works with existing JavaScript libraries Declaration files can be written and

maintained separately

Types enable tooling Provide verification and assistance, but not

hard guarantees

Type SystemAn accurate static representation of JavaScript’s dynamic run-time type system

Scalable application structuring Classes, interfaces, and modules enable clear contracts in

code

Aligned with emerging standards Class and lambda syntax aligns with ECMAScript 6 proposals

Supports popular module systems CommonJS and AMD modules in any ECMAScript 3

environment

Classes, Interfaces, ModulesAn accurate static representation of JavaScript’s dynamic run-time type system

Community 827 forks, 500 feature requests, 3.5K StackOverflow

questions Now taking pull requests – 1651 Closed already

Frameworks Over 1350 .d.ts library definitions on Definitely Typed

repository covering more than 95% of popular JavaScript frameworks

Tool support IDEs: VS, Monaco, Eclipse, IntelliJ, Resharper, Sublime, Atom,

Brackets Build: Heroku, Ruby, grunt, ASP.NET, node.js, compile-in-

client Testing: Chutzpah, tsUnit

TypeScript EcosystemAn Open Source language for large scale JavaScript development.

TypeScript 1.6 (stable) available now! 1.7 (Beta) available but with breaking changes

ES7 Async…await (for ES6), Polymorphic this, etc

TypeScript 2.0 wish list Additional features, e.g. async/await for ES3 + ES5

Roadmap details https://github.com/Microsoft/TypeScript/wiki/Roadmap

TypeScript Roadmap

Demo Time!

Questions before lunch.js??????

http://typescriptlang.org

Useful Links• TypeScript – official website• ES6 compatibility table• TypeScript GitHub Repo• TypeScript Roadmap• Use TypeScript with Sublime• Use TypeScript with VS Code