One language to rule them all: TypeScript - SDD Conference · One language to rule them all:...
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One language to rule them all: TypeScript Gil Fink CEO and Senior Consultant, sparXys
Transcript of One language to rule them all: TypeScript - SDD Conference · One language to rule them all:...
One language to rule them all:
TypeScript
Gil Fink
CEO and Senior Consultant, sparXys
About Me• sparXys CEO and Senior consultant
• Microsoft MVP in the last 8 years
• Pro Single Page Application Development (Apress) co-author
• 4 Microsoft Official Courses (MOCs) co-author
• GDG Rishon and AngularUP co-organizer
Agenda• The why
• TypeScript syntax and language features
• Building a simple end-to-end app with TypeScript
• Summary
Wait! JavaScript?
Are you nuts?
"JavaScript is the assembly language of the Web"
Erik Meijer
“You can write large programs in JavaScript. You
just can’t maintain them”
Anders Hejlsberg
Let’s Be Serious• JavaScript is really a powerful language:
o Functional
o Dynamic
o Can run everywhere
• Huge community
• Big eco-system
• Tools – IDEs, debuggers, test tools and etc.
The Alternatives• We have several alternatives:
• Hard core vanilla JavaScript development
• JavaScript transpilers
• CoffeeScript – http://coffeescript.org
• Dart – http://dartlang.org
• Clojurescript - https://github.com/clojure/clojurescript
• Script# - http://scriptsharp.com/
What is TypeScript?“TypeScript is a typed superset of JavaScript that compiles to
plain JavaScript” ~typescriptlang.org
Hello TypeScriptDemo
TypeScript is Very Flexible
Any Browser Any Host
Any OS Tool Support
Some TypeScript Key Features
Support standard
JavaScript code with
static typing
Encapsulation through classes
and modules
Support for constructors,
properties and functions
Interfaces and enumssupport
Lambda and generics support
Intellisenseand syntax checking
• Modules
• Classes
• Arrow functions
• Default parameters
• Destructuring
• Spread and rest
• Let and const
• for...of
• Object literal
methods
• Shorthand
properties
• Computed
properties
• Octal / binary
literals
• Symbols
• Template strings
Features from the near Future of
the Web (ES2015/6), Today
Choose your compilation scenario.
It is up to you!
From TypeScript to JavaScript
class Greeter {
greeting: string;
constructor(message: string) {
this.greeting = message;
}
greet() {
return “Hi," + this.greeting;
}
}
TypeScript Code JavaScript Code
TypeScriptCompiler
var Greeter = (function () {function Greeter(message) {
this.greeting = message;}Greeter.prototype.greet =
function () { return “Hi," + this.greeting;
};return Greeter;
})();
tsc.js
How Good is TypeScript’sOutput?
tsconfig.json• Enables to configure the compiler options:
o Target language (ES3, ES5, ES6)
o Module system (AMD, ES6, CommonJS and etc.)
o Source map generation
o Remove comments when compiling
o And more
tsconfig.jsonDemo
Some Important Side Notes
• All JavaScript code is TypeScript codeo Simply copy and paste
• All JavaScript libraries work with TypeScripto You will need a declaration file to work with the library
@Types
Demo
TypeScript Type Annotations
• You can add type annotations to variables and
functions
var str: string = ‘hello’; // str is annotated as string
function foo(name: string) : string { // parameter and function annotated
return ‘hello’ + name;
}
TypeScript Types
Type AnnotationsDemo
Classes and Interfaces• You can define classes (same as in ES2015)
• You can define interfaceso And implement them later
interface IGreeter {
greet(): void;
}
class Greeter implements IGreeter{
greeting: string;
greet() {
console.log(this.greeting);
}
}
var Greeter = (function () {
function Greeter() {
}
Greeter.prototype.greet = function () {
console.log(this.greeting);
};
return Greeter;
})();
Modules• Uses ES2015 modules syntax
export interface IGreeter {
greet(): void;
}
export class Greeter implements IGreeter {
greeting: string;
greet() {
console.log(this.greeting);
}
}
var Greeter = (function () {
function Greeter() {
}
Greeter.prototype.greet = function () {
console.log(this.greeting);
};
return Greeter;
}());
exports.Greeter = Greeter;
Classes, Modules and Interfaces
Demo
Building a Simple End-to-End App with
TypeScriptDemo
TypeScript Versions• TypeScript 1.0
• TypeScript 2.0
• Current version: TypeScript 2.3
What’s New in TypeScript2?
• Generators and Iteration for ES5/ES3
• Type-checking for JavaScript files
• Null- and undefined-aware types
• ES2017 Spread and Rest
• Improved any inference
• Tagged union types
• And a lot more
Questions?
Summary• Open source language that compiles into
JavaScript
• Key features:• Code encapsulation
• Maintainable code
• Tooling support
• Learn TypeScript today!
Resources• TypeScript – http://www.typescriptlang.org
• TypeScript Source Code -
https://github.com/Microsoft/TypeScript
• Definitely Typed –
https://github.com/borisyankov/DefinitelyTyped
• My Website – http://www.gilfink.net
• Follow me on Twitter – @gilfink
Thank You!
