     Object.prototype.toString.call xs
 
 # arr.unshift(element1, ..., elementN)
-unshift = uncurry (x) -> (xs) ->
+unshift = curry (x, xs) ->
   concat xs, [x]
 
 module.exports = { length, concat, every, filter, forEach, indexOf, join,

    (xs) -> xs.lastIndexOf x, fromIndex

# arr.map(callback[, thisArg])
map = uncurry (fn) -> (xs) ->
  xs.map fn

# arr.pop()

shift = slice 1

# arr.some(callback[, thisArg])
some = curry (fn, xs) ->
  xs.some fn

# arr.sort([compareFunction])
