Little Schemin' in CoffeeScript

neckbeard.coffee

car = (arr) ->
  arr[0]

cdr = (arr) ->
  arr[1..]

# Using for loop
map = (arr, func) ->
 func(r) for r in arr

# Using recursion
_map = (arr, func, result) ->
  result = result || []
  if arr.length == 0
    return result
  result.push func car(arr)
  _map cdr(arr), func, result
  
console.log map([1,2,3,4,5], (x) -> x * x)
console.log _map([1,2,3,4,5], (x) -> x * x)

# Using for loop
reduce = (arr, func, memo) ->
  memo = func(val, memo) for val in arr
  memo

# Using recursion
_reduce = (arr, func, memo) ->
  n = car arr
  unless n?
    return memo
  memo = func n, memo
  _reduce cdr(arr), func, memo

f = (a,b) -> a * b
console.log _reduce([1,2,3,4,5], f, 3)
console.log reduce([1,2,3,4,5], f, 3)

rember.coffee

car = (arr) ->
  arr[0]

cdr = (arr) ->
  arr[1..]

# This doesn't really work the same way as cons in Scheme
cons = (a, b) ->
  if a instanceof Array == false
    a = [a]
  if b.length == 0
    return a
  a.push car(b)
  cons a, cdr(b)

console.log cons(1, [2,3,4]) # [1,2,3,4]

rember = (a, list) ->
  if list.length == 0
    return a
  if car(list) == a
    return cdr list
  else
    cons car(list), rember(a, cdr(list))

console.log rember 'mint', ['lamb', 'chops', 'and', 'mint', 'flavored', 'mint', 'jelly']