var numbers = range(1, 10);
numbers = map(numbers, function (n) { return n * n });
numbers = reverse(numbers);
foreach(numbers, console.log);

/* output:

   100
   81
   64
   49
   36
   25
   16
   9
   4
   1
*/

Kodejuice:
Found this online, and it looks so impossible but its very much possible......so if you think youre a JavaScript Baddass/Ninja or wareva, here's the chance to prove urself right.


In fact, this isn't about JavaScript, but that's the context I've discussed it in. I encourage you to think about it in more programming languages. (are there languages in which this can't be done?)

The problem: define functions range, map, reverse and foreach, obeying the restrictions below, such that the following program works properly. It prints the squares of numbers from 1 to 10, in reverse order.

var numbers = range(1, 10);
numbers = map(numbers, function (n) { return n * n });
numbers = reverse(numbers);
foreach(numbers, console.log);

/* output:

   100
   81
   64
   49
   36
   25
   16
   9
   4
   1
*/

Restrictions

You must not use arrays. The square bracket characters, [ and ], are forbidden, as well as new Array.

You must not use objects. The curly braces, { and }, and the dot character (.) are forbidden. You may use curly braces for code blocks, but not for creating JavaScript objects.

Should go without saying, these functions must be generic and do what their name implies. They must not be hard-coded for the particular 1..10 example.

Feel free to define utilities; you don't have to restrict your program to these 4 functions. It does not matter how fast, small or elegant it is — if you can do it within the limitations above, I think you're an above-average programmer.

var range = Array.from(Array(11).keys());

Array.shift(range);
var numbers = Array.reverse(Array.map(range, function(value){
  return value * value;
}));

Array.forEach(numbers, logNumbers);

function logNumbers(v){
  console.log(v);
}

dhtml18:
Why are you guys like this? This is xmas, you ought to be killing turkeys, rams, goats, cows etc or at least eating one somewhere, but why?
You guys just wanna code year in, year out, no way, i am out of here, runs away at top speed!!!!!!!

godofbrowser:

var range = Array.from(Array(11).keys());

Array.shift(range);
var numbers = Array.reverse(Array.map(range, function(value){
  return value * value;
}));

Array.forEach(numbers, logNumbers);

function logNumbers(v){
  console.log(v);
}

Does this fit into your desired solution?

Note: i have tried to avoid using a "new Array" or the square brackets "[]" array declaration. I have also tried not to use the "numbers" var as an object which i know it is (everything in js is an object).

  function range(start, end) {

            var result = start.toString();
            while (start < end)
                result += "," + ((++start).toString());

            return result.split("," );

        }
        function map(arr, func) {         
         var temp = arr.slice(0, arr.length);//make a local copy

            //clear out the original array
            while (arr.length)
                arr.shift();

            while (temp.length)
                arr.push(func(temp.shift())); //send each element in temp to the callback and add the result back to arr
            return arr;
        }
        function reverse(arr) {

            return arr.reverse();
        }

        function foreach(arr, func) {
                
         while(arr.length )func.bind(console)(arr.shift());
        }

          function range(start, end) {

            var result = String(start);
            while (start < end)
                result += "," + String(++start);

            with (result) {
                return split("," );
            }


        }
        function map(arr, func) {
            var l, m, n, o;

            with (arr) {
                l = length;
                var temp = slice(0, l);//make a local copy

                //clear out the original array
                while (length)
                    shift();
            }

            m = 0;
            while ((m++) !== l) {
                with (temp) {
                    n = shift();
                }
                o = func(n);
                with (arr) {
                    push(o);               
               }
            }
            return arr;
        }
        function reverse(arr) {    
            with(arr) return reverse();
        }
        function foreach(arr, func) {
            var current, i=0,l;
            
            with(arr){
                l = length;
            }
            while ( (i++) !== l){
                
                with(arr){
                    current = shift();
                }
                func.bind(console)(current);
            }
            
        }

function jarvis(&$i, &$j, &$count) {
    //$j = 10, by default, equivalent to the max number
    //of the range;
    $rand = rand(1, 10);
    if ($j > 0) {
      //is the first instance of the generated random number = 10 ? (print the number) : (keep looping through);
      if (($rand == max(range(1, 10))) && ($count == 0)) {
        print pow($rand, 2) . '<br />';
        $j--;
        $i = $rand;
        $count++;
        jarvis($i, $j, $count);
      } else if ($rand == $j) {
        //check if it's the next instance whose product
        //should be printed; is instance consecutive?
        print pow($rand, 2) . '<br />';
        $j--;
        $i = $rand;
        jarvis($i, $j, $count);
      } else {
        //keep loopin through if the nth instance is not consecutive
        //wrt to the previous
        jarvis($i, $j, $count);
      }
    }
  }
  
  function ironMan() {
    $i = 0;
    $j = 10;
    $count = 0;
    //the $i parameter is not necessary, just included in function construct in case
    //you wanna track the random number  
    jarvis($i, $j, $count);
  }
  ironMan();

paranorman:
i did PHP, using a recursive function, Mr. kodejuice

function jarvis(&$i, &$j, &$count) {
    //$j = 10, by default, equivalent to the max number
    //of the range;
    $rand = rand(1, 10);
    if ($j > 0) {
      //is the first instance of the generated random number = 10 ? (print the number) : (keep looping through);
      if (($rand == max(range(1, 10))) && ($count == 0)) {
        print pow($rand, 2) . '<br />';
        $j--;
        $i = $rand;
        $count++;
        jarvis($i, $j, $count);
      } else if ($rand == $j) {
        //check if it's the next instance whose product
        //should be printed; is instance consecutive?
        print pow($rand, 2) . '<br />';
        $j--;
        $i = $rand;
        jarvis($i, $j, $count);
      } else {
        //keep loopin through if the nth instance is not consecutive
        //wrt to the previous
        jarvis($i, $j, $count);
      }
    }
  }
  
  function ironMan() {
    $i = 0;
    $j = 10;
    $count = 0;
    //the $i parameter is not necessary, just included in function construct in case
    //you wanna track the random number  
    jarvis($i, $j, $count);
  }
  ironMan();

stack1:
...So this is version 2, i removed all but one dot operator, i couldn't find an alternative for the
last dot operator in the foreach function so..
(and i know, the with operator feels like a cheat)

          function range(start, end) {

            var result = String(start);
            while (start < end)
                result += "," + String(++start);

            with (result) {
                return split("," );
            }


        }
        function map(arr, func) {
            var l, m, n, o;

            with (arr) {
                l = length;
                var temp = slice(0, l);//make a local copy

                //clear out the original array
                while (length)
                    shift();
            }

            m = 0;
            while ((m++) !== l) {
                with (temp) {
                    n = shift();
                }
                o = func(n);
                with (arr) {
                    push(o);               
               }
            }
            return arr;
        }
        function reverse(arr) {    
            with(arr) return reverse();
        }
        function foreach(arr, func) {
            var current, i=0,l;
            
            with(arr){
                l = length;
            }
            while ( (i++) !== l){
                
                with(arr){
                    current = shift();
                }
                func.bind(console)(current);
            }
            
        }

// helper functions
function cons(x, y) {
    return function(f) { return f(x, y) };
}

function car(pair) {
    return pair(function(x, y){ return x });
}

function cdr(pair) {
    return pair(function(x, y){ return y });
}

function nil(f) {
    return f(nil, nil);
}

// ....
function range(start, stop) {
    return start <= stop ? cons(start, range(start + 1, stop)) : nil;
}

function map(list, func) {
    return list === nil ? nil : cons(func(car(list)), map(cdr(list), func));
}

function foreach(list, func) {
    if (list !== nil) {
        func(car(list));
        foreach(cdr(list), func);
    }
}

function reverse(list) {
    return (function rev(list, ret){
        return list === nil ? ret : rev(cdr(list), cons(car(list), ret));
    })(list, nil);
}

Kodejuice:


LoL, u try sha, anyway heres my solution

// helper functions
function cons(x, y) {
    return function(f) { return f(x, y) };
}

function car(pair) {
    return pair(function(x, y){ return x });
}



function cdr(pair) {
    return pair(function(x, y){ return y });
}

function nil(f) {
    return f(nil, nil);
}

// ....
function range(start, stop) {
    return start <= stop ? cons(start, range(start + 1, stop)) : nil;
}

function map(list, func) {
    return list === nil ? nil : cons(func(car(list)), map(cdr(list), func));
}

function foreach(list, func) {
    if (list !== nil) {
        func(car(list));
        foreach(cdr(list), func);
    }
}

function reverse(list) {
    return (function rev(list, ret){
        return list === nil ? ret : rev(cdr(list), cons(car(list), ret));
    })(list, nil);
}

Kodejuice:


(WTF)

paranorman:
i did PHP, using a recursive function, Mr. kodejuice

function jarvis(&$i, &$j, &$count) {
    //$j = 10, by default, equivalent to the max number
    //of the range;
    $rand = rand(1, 10);
    if ($j > 0) {
      //is the first instance of the generated random number = 10 ? (print the number) : (keep looping through);
      if (($rand == max(range(1, 10))) && ($count == 0)) {
        print pow($rand, 2) . '<br />';
        $j--;
        $i = $rand;
        $count++;
        jarvis($i, $j, $count);
      } else if ($rand == $j) {
        //check if it's the next instance whose product
        //should be printed; is instance consecutive?
        print pow($rand, 2) . '<br />';
        $j--;
        $i = $rand;
        jarvis($i, $j, $count);
      } else {
        //keep loopin through if the nth instance is not consecutive
        //wrt to the previous
        jarvis($i, $j, $count);
      }
    }
  }
  
  function ironMan() {
    $i = 0;
    $j = 10;
    $count = 0;
    //the $i parameter is not necessary, just included in function construct in case
    //you wanna track the random number  
    jarvis($i, $j, $count);
  }
  ironMan();

Kodejuice:


LoL, u try sha, anyway heres my solution

// helper functions
function cons(x, y) {
    return function(f) { return f(x, y) };
}

function car(pair) {
    return pair(function(x, y){ return x });
}

function cdr(pair) {
    return pair(function(x, y){ return y });
}

function nil(f) {
    return f(nil, nil);
}

// ....
function range(start, stop) {
    return start <= stop ? cons(start, range(start + 1, stop)) : nil;
}

function map(list, func) {
    return list === nil ? nil : cons(func(car(list)), map(cdr(list), func));
}

function foreach(list, func) {
    if (list !== nil) {
        func(car(list));
        foreach(cdr(list), func);
    }
}

function reverse(list) {
    return (function rev(list, ret){
        return list === nil ? ret : rev(cdr(list), cons(car(list), ret));
    })(list, nil);
}

Craigston:



Someday these guys are gonna hatch monsters...

dhtml18:

Are you sure these people are human beings like this? Me, right now, all I can see is turkey, chicken and monitor lizard anywhere i look, no time for coding again o!

stack1:


Monitor Lizard, hahaha

Craigston:



Someday these guys are gonna hatch monsters...

dhtml18:
i dont even know what range means here abi na range wey them teach us for statistics? i don fly fence go play playstation that day

paranorman:

Hahahahaha, I pray so Bros. I am still a rookie sha.

the op was going on about using range, functions bla, bla, bla...

I just solved his problem using a single function, the second function wasn't even necessary.

Craigston:

U neva see anything. NA Physics o. Projectiles. One of them don write Jarvis sef (Paranorman). I just tire. Abeg who sabi cook snake wella? My neighbor wan dash me python. E fat ehn! I just want the snake roasting algorithm.

Craigston:

Your approach might take more time to run. Figure out the cause.
Hint: recursive guessing.

dhtml18:

We need picture of the snake, we shall invite lala to cook it for us, how these BOTS are managing to write all these codes in this festive period beats me.

paranorman:

Hahahahaha, I pray so Bros. I am still a rookie sha.

the op was going on about using range, functions bla, bla, bla...

I just solved his problem using a single function, the second function wasn't even necessary.

stack1:
any more??

dhtml18:

At least Lala dey chop am for FP everything, the reason most threads on this board no dey reach FP na because them no get monitor lizard. If someone here comes up with a code that actually catches a monitor lizard, FP straight. . . .