davejachimiak

var Evented;

Evented = {
  on: function(event, callback) {
    var _base;
    (_base = this.callbacks)[event] || (_base[event] = []);
    return this.callbacks[event].push(callback);
  },
  trigger: function(event) {
    var args, callbacks;

davejachimiak

-- SICP 1.12
--
-- The following pattern of numbers is called Pascal's triangle.
--
--      1
--     1 1
--    1 2 1
--   1 3 3 1
--  1 4 6 4 1
--     ...

davejachimiak

-- SICP 1.11
--
-- A function f is defined by the rule that f(n) = n if n < 3 and
-- f(n) = f(n - 1) + 2f(n - 2) + 3f(n - 3) if n >= 3. Write a
-- procedure computes f by means of a recursive process.
--
f :: Integer -> Integer
f n
    | n < 3 = n
    | otherwise = f (n - 1) + 2 * f (n - 2) + 3 * f (n - 3)

davejachimiak

countChange :: Integer -> [Integer] -> Integer
countChange amount denominations
    | null denominations || amount < 0 = 0
    | amount == 0 = 1
    | otherwise = countChange amount (tail denominations) + countChange (amount - head denominations) denominations