isInOrder.js

var isInOrder = function(){
  var args = Array.prototype.slice.call(arguments)

  for ( var i = 0, len = args.length; i < len - 1; i += 1) if ( args[i] > args[i + 1] ) return false
  return true
}


var identity = function(a){ return a }
var f = identity


isInOrder(1, f(2), 2) //= true
isInOrder(1, f(2), 3) //= true
isInOrder(1, f(-2), 3) //= false