lunchvoting.js

// Original code in Scheme, from
// <http://www.cap-lore.com/CapTheory/Language/lambdaSecurity.html>:
//
// (define (mocntr) (let ((x 0)) (cons (lambda () (let ((yet #t))
//      (lambda () (if yet (begin (set! yet #f) (set! x (+ 1 x)) x)))))
//   (lambda () x))))
// (define restaurants (list "Mandarin" "Casa Lupe" "Coffee Shop"))
// (define (noontime) (let ((bb
//        (map (lambda(r) (cons r (mocntr))) restaurants)))
//     (for-each (lambda (e) ((cdr e) (cons "Lunchtime!" (map
//       (lambda(r)(cons (car r) ((cadr r)))) bb)))) lunchAgents)
//     (lambda ()(map (lambda(x) (cons (car x) ((cddr x)))) bb))))
// (define lunchcrowd (list 'Jim 'Sue 'Tom 'Jennifer))
// 
// (define lunchAgents (map (lambda (eater) (let ((cell
//     (cons eater (lambda (ballot) '()))))
//   ('send eater "LunchAgentAppointer"
//   (lambda (agent) (set-cdr! cell agent))) cell)) lunchcrowd))


function mocntr() {
 var x = 0;
 return { voterMaker: function() {
            var yet = true;
            return function() {
              if (!yet) return;
              yet = false;
              x++;
              return x;
            };
          }
        , votes: function() {
            return x;
          }
        };
}
var restaurants = ["Mandarin", "Casa Lupe", "Coffee Shop"];
var lunchCrowd = ['Jim', 'Sue', 'Tom', 'Jennifer'];

var lunchAgents = [];
for (var ii = 0; ii < lunchCrowd.length; ii++) {
  var eater = lunchCrowd[ii];
  lunchAgents.push((function() {
     var cell = { eater: eater, ballotReceiver: function(ballot) {} };
     SEND(eater, "LunchAgentAppointer",
          function(agent) { cell.ballotReceiver = agent });
     return cell;
   })());
}

function noontime() {
  var bb = [];
  for (var ii = 0; ii < restaurants.length; ii++) {
    (function() {
       var restaurant = restaurants[ii];
       bb.push({restaurant: restaurant, counter: mocntr()});
     })()
  }
  for (ii = 0; ii < lunchAgents.length; ii++) {
    var e = lunchAgents[ii]
      , ballot = []
    ;
    for (var jj = 0; jj < bb.length; jj++) {
      ballot.push({ restaurant: bb[jj].restaurant
                  , vote: bb[jj].voterMaker()
                  });
    }
    e.send(["Lunchtime!", ballot]);
  }

  return function() {
    var votes = [];
    for (var ii = 0; ii < bb.length; ii++) {
      votes.push({ restaurant: bb[ii].restaurant
                 , votes: bb[ii].counter.votes()
                 });
    }
    return votes;
  };
}

Still fixing some bugs... and rewriting in CoffeeScript!

Okay. There are still bugs in the JS version. The CS version is at https://gist.github.com/3429195.