Company techsession around LiveScript, and the benefits of langs like Coffee and Live over Javascript directly

1. L I V E S C R I P T
( O R / [ C O F F E E ] | [ L I V E ] S C R I P T / G )
R O C K I N G Y O U R W O R L D . J S
Copyright 2014 - Synthesis Software Technology
http://www.synthesis.co.za

2. J S = F T W & & W T F

4. Type coercion strangely-ness
[1,2,3] + [5,6,7] = “1,2,35,6,7”
{} + [] = “[object Object]”
{} - [] = NaN

5. > typeof NaN
> ?

6. var x = 500
vs.
x = 500

7. for (x in [3,4,5]) {
console.log(x);
}

8. for (x in {1:2,3:4}) {
console.log(x);
}

9. Q U I Z
Which of the following is NOT a usable
javascript keyword:
a. var
b. with
c. in
d. class
e. undefined

10. JavaScript keywords:
break, case, catch, continue, debugger, default, delete, do, else,
false, finally, for, function, if, in, instanceof, new, null, return,
switch, this, throw, true, try, typeof, var, void, while, with.
Reserved for future use:
abstract, boolean, byte, char, class, const, double, enum, export,
extends, final, float, goto, implements, import, int, interface,
let, long, native, package, private, protected, public, short,
static, super, synchronized, throws, transient, volatile, yield.
Reserved for browser:
alert, blur, closed, document, focus, frames, history, innerHeight,
innerWidth, length, location, navigator, open, outerHeight,
outerWidth, parent, screen, screenX, screenY, statusbar, window.

11. S P O T T H E B U G !
var car = {
state: "off",
start: function() {
this.state = "starting";
setTimeout(function() {
this.state = "started"
}, 1000);
}
};
car.start();

12. P R O T O T Y P A L O O S T Y L E
var Person = function(name) {
return {
name: name,
getname: function() {
return this.name.toUpperCase();
}
}
}
var peter = new Person("Peter");
peter.getname();
var luke = { name: “Luke” };
luke.getname = peter.getname;
luke.getname();
var crazy = peter.getname;
crazy(); // ??

13. null !== undefined

14. [coffee|live|type]script

15. A W H I R L A R O U N D C O F F E E
S C R I P T
syntax
scope
variables
functions
templating
list comp.
== vs. ===

16. lsc ~= coffee + x

17. F A T T Y G O O D N E S S
fix coffee’s weirdly-ness (like ‘=‘and list comps)
spicy curry and nice
ninja |> <| >> << operators
async backcalls
A N D B A T T E R I E S !
prelude
more scary compiled js
could be a gateway drug… >:-0
D O W N S I D E S O V E R C O F F E E ?