javascript : what is it really? and some new features in es6

JSUHMMM..

JAVASCRIPT

@AayushShrestha

Co-Founder - LISHN

Head of Experience Design & Architecture -Viveka Health

fb.me/ShresthaAayush

aayushonweb@gmail.com

• What is JavaScript, really?

• What’s all the fuss about?

• ES6 / ES2015 / ECMAScript 2015

The world’s most

popular language.

POPULARITY STACK OVERFLOW VS GITHUB

STACK OVERFLOW TAG NAME TRENDS

RANKED BY # OF PROGRAMMING JOBS

The world’s most

unpopular language.

BRENDEN EICH

JAVA SCHEME SELF

LiveScript

JavaScript

ECMAScript

The web was a disappointment

as an application delivery

system in 2000s.

- Page replacement inefficient.

- Java Applets FAILED!

- Nobody believed in JavaScript.

The web is dead.

-People of early 2000

Microsoft

abandoned web.

AJAX

-JavaScript gets a second chance.

PLENTY OF REASONS TO HATE JAVASCRIPT

• It has bad parts. REALLY REALLY BAD PARTS.

• Slow execution.

• DOM is a headache.

• It’s not C, C#, Java, Python, Ruby….

• It does not go away.

JavaScript has

good parts.

That’s why you like it.

JavaScript is a functional

language with dynamic

objects and familiar syntax.

Scales from

beginners to masters.

Very effective in an event-

driven application model.

Programs can be significantly

smaller compared to equivalent

program in other languages.

Always evolving and

proving people wrong.

JAVASCRIPT IS EVERYWHERE

JAVASCRIPT IS EVERYWHERE

• Browsers

• Applications

• OS

• Databases

• Mobile

• Electronics

• Servers

— Jeff Atwood (2007)

Any application that can be written

in javascript, wil l eventually be

written in javascript

”

“ATWOOD’S LAW

Can JavaScript become

a better language?

YES!!

The most effective way is

to remove the bad parts.

DUH!!

Write code that not only

works, but looks correct too.

JS will become better if we use it

better.

ES2015

Faster. easier. Better.

MAIN GOALS OF ES6

• Fix (some of) ES5 issues

• Backwards Compatibility

• Modern Syntax

• Better suited for big applications

• New features

- Transpiler

- Converts future JS to working JS

Some

ES6/ES2015

Features

LET’S WRITE SOME ES6!

:)

LET

CONST

TEMPLATE STRINGS

CLASSES

CLASSES : INHERITANCE

CLASSES : GETTER/SETTER

ARROW FUNCTIONS

DESTRUCTURING

DESTRUCTURING

MORE COOL STUFFS

• Modules

• Promises

• Symbols

• Generators

• Map/Set Weakmap/Weakset

• More libraries and Core functions extension

REFERENCES

• David Crockford’s talk “Really. JavaScript”

• http://es6-features.org/

@AayushShrestha

QUESTIONS?

fb.me/ShresthaAayush

aayushonweb@gmail.com