Javascript questions

js-questions.js

// Function closures:

var fn = function(x) {
  return function() { return x = x + 1; };
};

var fn2 = fn(2);  
// Q. What is stored in the variable fn2? 
// A. A function which, when called, increments x by 1 and returns the result.
//    A common mistake is to think it returns either 2, or 3.

// Q. What is the return value of running:
fn2(); // => 3
fn2(); // => 4
fn2(); // => 5

// They should know at least that fn(2) returns a function.  
// If they are fuzzy on how x maintains state (keeps increasing), that's OK, but not great.


// common js idioms: