Revision 1749, 2.2 kB
(checked in by nishio, 9 years ago)

lang/unlambda/impl/in_python: brandnew version to support call/cc[c], currently supports [`.xi]

Line  

1  """ unlambda interpreter


2 


3  # test


4  >>> run("`.ai")


5  a


6 


7  """


8  globals().clear()


9  # Main loop


10  #


11  def run(s):


12  task = EvalTask(parse(s), FinalCont)


13  try:


14  while True:


15  task = task()


16  except StopIteration, e:


17  return


18 


19  # Continuation


20  # __call__(Func) returns Task


21  def FinalCont(f):


22  def FinalTask():


23  raise StopIteration


24  return FinalTask


25 


26  # Task


27  #


28  class Task(object): pass


29 


30  def EvalTask(node, cont):


31  def run():


32  return node.eval(cont)


33  return run


34 


35  # Node


36  #


37  class Node(object):


38  "parsed element"


39 


40  class I(Node):


41  "identity"


42  def eval(self, cont):


43  def I0(X, cont):


44  return cont.invoke(X)


45  return cont(I0)


46 


47  class Dot(Node):


48  "print char: `.aX => print 'a'"


49  def __init__(self, c):


50  self.c = c


51  def eval(self, cont):


52  def Dot0(X, cont):


53  import sys


54  sys.stdout.write(self.c)


55  return cont(X)


56  return cont(Dot0)


57 


58  class Apply(Node):


59  "apply: `FG = F(G)"


60  def __init__(self, X, Y):


61  "take 2 notevaluated node"


62  self.nX = X


63  self.nY = Y


64  def eval(self, cont):


65  nY = self.nY


66  def next(X):


67  def _App1(): # task


68  "evalated X and notevaluated Y"


69 


70  # if X.isDelay:


71  # return self.cont.invoke(D1Function(self.nY))


72 


73  def next(Y):


74  def _App2(): # task


75  return X(Y, cont)


76  return _App2


77  return nY.eval(next)


78  return _App1


79  return EvalTask(self.nX, next)


80 


81  def _parse(iter):


82  c = iter.next()


83  result = {


84  "i": lambda: I(),


85  ".": lambda: Dot(iter.next()),


86  "`": lambda: (lambda f=_parse(iter): Apply(f, _parse(iter)))(),


87 


88  "r": lambda: R(),


89  "v": lambda: V(),


90  "d": lambda: "(delay)", # special form


91  "c": lambda: C(),


92  "s": lambda: S(),


93  "k": lambda: K(),


94  }.get(c, lambda: _parse(iter))()


95  return result


96 


97  def parse(s):


98  return _parse(list(s).__iter__())


99 


100  def _test():


101  import doctest


102  reload(doctest)


103  doctest.testmod()


104 


105  run("`.ai")

