TypeScript
Udaiappa Ramachandran ( Udai )
//linkedin.com/in/udair
Who am I?
• Udaiappa Ramachandran ( Udai )
• CTO, Akumina, Inc.,
• Consultant
• Azure Insider
• New Hampshire Cloud User Group (http://www.meetup.com/nashuaug )
• Focus on Cloud Computing (Microsoft Azure and AWS), IoT, SharePoint
Online
• http://cloudycode.wordpress.com
• @nhcloud
TypeScript - Agenda
• Why & What
• Basic Types
• Interfaces
• Functions
• Classes
• Generics
• Modules
• Demo
• References
• Q & A
Typescript
• Why
• Javascript is dynamic type
• Pro– can hold any object, type on the fly
• Con- Can get messy over the time
• Migration from server-side to client-side will be hard
• Hard to manage, difficult to ensure property types
• What
• Any valid JavaScript is a typescript
• Typescriptlang.org
• Typescript lets you write JavaScript the way you really want to.
• Typescript is a typed superset of JavaScript that compiles to plain JavaScript.
• Any browser. Any host. Any OS. Open Source.
Typescript Alternatives
• Pure JavaScript
• Apply JavaScript patterns
• Functions as abstractions
• Functions to build modules
• Functions to avoid global variables
• CoffeeScript
• Dart
Typescript Key Features
• Supports standard JavaScript code
• Provide static typing
• Encapsulation through classes and modules
• Support for constructors, properties, functions
• Define interfaces
• Lambda style function support
• Intellisense and syntax checking
Typescript tools
• Typescript playground
• Visual Studio
• sublime
• Node.js
• WebStorm
• Eclipse
• Vi
• IntelliJ
• Emacs
Typescript to JavaScript
Tyepscript BasicTypes
• Boolean
• Number
• String
• Array
• Enum
• Enum as Bit Flag 1,2,4,8,16,32,64,128 and so on
• Any
• Void
Tyepscript Annotation
• Type Annotation
• var [identifier]:[type annotation]=value
• var [identifier]:[type annotation];
• var [identifier]=value;
• Example
Typescript Functions
• Optional Parameters using ?
• function getAverage(a: number, b: number, c?: number): void { }
• Default parameters using =value
• function concatenate(items: string[], separator = ",", beginAt = 0, endAt = items.length) :void{ }
• Rest parameter using …
• Only one allowed, it must appear last in the parameter list and must be an array type
• function getSum(...a: number[]): number {
• var t = 0;a.forEach(p=>t=t+ p);
• return t;
• }
• var result = getSum(1, 2, 3, 4);
• Overloads
• Overloads in typescript cannot have own implementation but decorate a single implementation
• function getSum(a: string, b: string, c: string): number;
• function getSum(a: number, b: number, c: number): number;
• function getSum(a: any, b: any, c: any): number {
• // implementation signature
• return parseInt(a, 10) + parseInt(b, 10) + parseInt(c, 10);
• }
• Arrow function
• var getSum: (a: number, b: number) => number =(x, y) => (x + y);
Typescript Interfaces
• Interfaces are used at design time to provide auto completion and at compile time
to provide type checking
• Supported features
• Optional properties
• Function Types
• Array Types
• Class Types
• Extending Interfaces
• Hybrid Types
Typescript Interfaces
Typescript Classes
• Object-oriented class based approach
• Key features
• Inheritance
• Private/public modifiers
• Accessors
• Static properties
• Constructor functions
• Using class as an interface
Typescript Classes
Typescript Generics
• Supports generic type variables, types, interfaces, classes and constraints
Typescript Modules
• Encapsulate variables, interfaces, and classes
• Define unique namespaces
• Organize symbols and identifiers into a logical namespace hierarchy
• Similar to namespaces/packages
• Splitting across files
• Multiple files can use the same module name
• One file can contain multiple module
• Can define Alias to module
• Transpiles to IIFE
• Can define modules as internal or external
• External modules required only when used with node.js and require.js
Typescript Modules
Typescript Declaration Merging
• Concept
• Merging Interfaces
• Merging Modules
• Merging Modules with classes, functions, and Enums
• Disallowed Merges
Typescript Type inference and Compatibility
• Type inference
• Basics
• Best common type
• Contextual Type
• Type Compatibility
• Starting out
• Comparing two functions
• Enums
• Classes
• Generics
• Advanced Topics
• Common Errors
• Mixins
Typescript Definition Files
• Describes the types defined in external libraries
• .d.ts
• Not deployed
• Usually from DefinitelyTyped
• TypeScript Definition manager (tsd)
• Specialized package manager
• Locates and installs typescript definition files(d.ts)
• From the definitelytyped repository
Demo
Reference
• //typescriptlang.org
Q & A

TypeScript

  • 1.
    TypeScript Udaiappa Ramachandran (Udai ) //linkedin.com/in/udair
  • 2.
    Who am I? •Udaiappa Ramachandran ( Udai ) • CTO, Akumina, Inc., • Consultant • Azure Insider • New Hampshire Cloud User Group (http://www.meetup.com/nashuaug ) • Focus on Cloud Computing (Microsoft Azure and AWS), IoT, SharePoint Online • http://cloudycode.wordpress.com • @nhcloud
  • 3.
    TypeScript - Agenda •Why & What • Basic Types • Interfaces • Functions • Classes • Generics • Modules • Demo • References • Q & A
  • 4.
    Typescript • Why • Javascriptis dynamic type • Pro– can hold any object, type on the fly • Con- Can get messy over the time • Migration from server-side to client-side will be hard • Hard to manage, difficult to ensure property types • What • Any valid JavaScript is a typescript • Typescriptlang.org • Typescript lets you write JavaScript the way you really want to. • Typescript is a typed superset of JavaScript that compiles to plain JavaScript. • Any browser. Any host. Any OS. Open Source.
  • 5.
    Typescript Alternatives • PureJavaScript • Apply JavaScript patterns • Functions as abstractions • Functions to build modules • Functions to avoid global variables • CoffeeScript • Dart
  • 6.
    Typescript Key Features •Supports standard JavaScript code • Provide static typing • Encapsulation through classes and modules • Support for constructors, properties, functions • Define interfaces • Lambda style function support • Intellisense and syntax checking
  • 7.
    Typescript tools • Typescriptplayground • Visual Studio • sublime • Node.js • WebStorm • Eclipse • Vi • IntelliJ • Emacs
  • 8.
  • 9.
    Tyepscript BasicTypes • Boolean •Number • String • Array • Enum • Enum as Bit Flag 1,2,4,8,16,32,64,128 and so on • Any • Void
  • 10.
    Tyepscript Annotation • TypeAnnotation • var [identifier]:[type annotation]=value • var [identifier]:[type annotation]; • var [identifier]=value; • Example
  • 11.
    Typescript Functions • OptionalParameters using ? • function getAverage(a: number, b: number, c?: number): void { } • Default parameters using =value • function concatenate(items: string[], separator = ",", beginAt = 0, endAt = items.length) :void{ } • Rest parameter using … • Only one allowed, it must appear last in the parameter list and must be an array type • function getSum(...a: number[]): number { • var t = 0;a.forEach(p=>t=t+ p); • return t; • } • var result = getSum(1, 2, 3, 4); • Overloads • Overloads in typescript cannot have own implementation but decorate a single implementation • function getSum(a: string, b: string, c: string): number; • function getSum(a: number, b: number, c: number): number; • function getSum(a: any, b: any, c: any): number { • // implementation signature • return parseInt(a, 10) + parseInt(b, 10) + parseInt(c, 10); • } • Arrow function • var getSum: (a: number, b: number) => number =(x, y) => (x + y);
  • 12.
    Typescript Interfaces • Interfacesare used at design time to provide auto completion and at compile time to provide type checking • Supported features • Optional properties • Function Types • Array Types • Class Types • Extending Interfaces • Hybrid Types
  • 13.
  • 14.
    Typescript Classes • Object-orientedclass based approach • Key features • Inheritance • Private/public modifiers • Accessors • Static properties • Constructor functions • Using class as an interface
  • 15.
  • 16.
    Typescript Generics • Supportsgeneric type variables, types, interfaces, classes and constraints
  • 17.
    Typescript Modules • Encapsulatevariables, interfaces, and classes • Define unique namespaces • Organize symbols and identifiers into a logical namespace hierarchy • Similar to namespaces/packages • Splitting across files • Multiple files can use the same module name • One file can contain multiple module • Can define Alias to module • Transpiles to IIFE • Can define modules as internal or external • External modules required only when used with node.js and require.js
  • 18.
  • 19.
    Typescript Declaration Merging •Concept • Merging Interfaces • Merging Modules • Merging Modules with classes, functions, and Enums • Disallowed Merges
  • 20.
    Typescript Type inferenceand Compatibility • Type inference • Basics • Best common type • Contextual Type • Type Compatibility • Starting out • Comparing two functions • Enums • Classes • Generics • Advanced Topics • Common Errors • Mixins
  • 21.
    Typescript Definition Files •Describes the types defined in external libraries • .d.ts • Not deployed • Usually from DefinitelyTyped • TypeScript Definition manager (tsd) • Specialized package manager • Locates and installs typescript definition files(d.ts) • From the definitelytyped repository
  • 22.
  • 23.
  • 24.

Editor's Notes

  • #5 Typescript will still try to create sensible JS code even if compilation error, but it is important to fix the compilation error
  • #20  Module merging Class Car{ } Module Car { Export Engine{} Export XYZ{} }
  • #22 IIFE-Immediately Invoked Function Expressions