Create ls command for Windows cmd

In order to enable cmd on Windows run ls command just run from command line this:

echo dir %1 > %systemroot%\system32\ls.bat

Javascript D3 good basic explanation

http://synthesis.sbecker.net/articles/2012/07/08/learning-d3-part-1

JavaScript D3 - example how the function(d, i) works

http://jsfiddle.net/M8nK8/

==HTML==
<script src="http://d3js.org/d3.v3.min.js"></script>
<section></section>


===JS D3==

var data=[10,20,30,40];

var lis = d3.select("section")
          .append("ul")
            .selectAll("li")
            .data(data)

lis.enter()
 .append("li")
 .text(function(d,i){ return "item n° "+i+" has value: "+d})

JavaScript D3 - forEach() vs each() function

The main takeaway is that, using .each() you get access to 3 things you need: d, this and i. With .forEach(), on an array (like in the example from the beginning) you only get 2 things (d and i), and you'd have to do a bunch of work to also associate an HTML element with those 2 things. And that, among other things, is how d3 is useful.

http://stackoverflow.com/questions/13465796/d3-javascript-difference-between-foreach-and-each