Sunday, October 6, 2013

JS Essentials talk

Travis Tidwell

dynamically typed with var
everything is object including primitives
functions are first class objects treated just like any other variable
OO, procedural, functional

Use JSON notation in defining objects, arryays var v = ['test'];
Object - unordered collection key value pairs
decalre functions like a variable with equals - var myfunction = function () {}
Use functions to encapsulate context such as with the 'this'

Here is an example of a closure:

var colors = ['red' , 'blue', 'yellow' ] ;

console.log('number of colors ' + colors.length);

for (var i=0;i<colors.length;i++){
setTimeout ((function(i){
               return function (){
     console.log(i) ;

             }) (i), 100);

Function scope or Global scope
this keyword - owner of function we are executing
variable must be assigned to something for it to have 'this' meaning

prototype - is an object in which other objects inherits properties
every object has one
__proto__ in the debugger
Use it to define the blue print of the class


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