I just read a great article about JavaScript Scoping and Hoisting by Ben Cherry in which he gives the following example:
var a = 1;
function b() {
a =
Here's my recap of the answer with more annotation and an acompaniying fiddle to play around with.
// hoisting_example.js
// top of scope ie. global var a = 1
var a = 1;
// new scope due to js' functional (not block) level scope
function b() {
a = 10; // if the function 'a' didn't exist in this scope, global a = 10
return; // the return illustrates that function 'a' is hoisted to top
function a(){}; // 'a' will be hoisted to top as var a = function(){};
}
// exec 'b' and you would expect to see a = 10 in subsequent alert
// but the interpreter acutally 'hoisted' the function 'a' within 'b'
// and in doing so, created a new named variable 'a'
// which is a function within b's scope
b();
// a will alert 1, see comment above
alert(a);
https://jsfiddle.net/adjavaherian/fffpxjx7/