I'm studying function closures from http://ift.tt/1vKs8WG
I don't understand the below code. variable add refers to a self-invoking anonymous function which returns an anonymous function. In this case, what happens to variable counter? when we call function add, what happens?
<!DOCTYPE html>
<html>
<body>
<p>Counting with a local variable.</p>
<button type="button" onclick="myFunction()">Count!</button>
<p id="demo">0</p>
<script>
var add = (function () {
var counter = 0; })();
return function () {return counter += 1;}
function myFunction(){
document.getElementById("demo").innerHTML = add();
}
</script>
</body>
</html>
in addition I dont understand why the code below does not work?
<!DOCTYPE html>
<html>
<body>
<p>Counting with a local variable.</p>
<button type="button" onclick="myFunction()">Count!</button>
<p id="demo">0</p>
<script>
var add = (function () {
var counter = 0;
return function ()
{
var semih=0;
if(counter >5)
{
return function(){ semih += 5; }
}
return counter += 1;}
}
)();
function myFunction(){
document.getElementById("demo").innerHTML = add();
}
</script>
</body>
</html>
via Chebli Mohamed
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