gistfile1.txt

define ["jquery", "underscore", "barista"], ($, _, B) ->
  outs = B.createModule()
  #Define a protocol
  IStack = outs.defTypeclass 'IStack', (self) -> {
    push: self.Abstract
    pop: self.Abstract
    pushAll : (elems...) -> _(elems).forEach((elem) -> self.push(elem))
  }

  #Make an implementation for arrays.
  outs.implementTypeclass IStack, (x, ys...) -> $.isArray(x) && ys.length == 0,
  {
    push :(elem) -> @.push(elem)
    pop :() -> [@, @.pop()]
  }

  outs.export()