javascript_scoping

javascript_scoping.js

/*
  GLOBAL SCOPE
*/
var global_var = "mango"; // global_var is accessible everywhwere

/*
  Function scope is lexical
*/
function otherFunction() {
  var outer_var = "foo";
  // inner_var is not accessible here
  function innerFunction() {
    var inner_var = "bar";
    // outer_var is accessible here
  }
}

/*
  Using function scope to create a closure
*/
function closure_maker() {
  var closure_var = 'remember_me';
  return function() {
    return closure_var;
  }
}
closure = closure_maker();
closure(); //=> 'remember_me';

/*
 Blocks have the same scope as their containing scope.
*/
if (true) {
  var block_var = 'wat';
}
block_var // => 'wat'

for(var i=0; i < 10; i++){
  console.log("hello block scope");
}
i //=> 10