gistfile1.py

import itertools

class SingleMix(object):
    def __init__(self, x): self._x = x
    def __repr__(self): return "%s(%r)" % (self.__class__.__name__, self._x)

class InfixMix(object):
    def __init__(self, left, right):
        self._left = left
        self._right = right
    def __repr__(self):
        return "(%r %s %r)" % (self._left, self.__class__.op, self._right)

class Processor:
    def __rshift__(self, other):
        return ProcessorComposite(self, other)

class ProcessorComposite(Processor, InfixMix):
    op = ">>"
    __init__ = InfixMix.__init__
    def __call__(self, stream):
        return self._right(self._left(stream))

class Map(Processor, SingleMix):
    __init__ = SingleMix.__init__
    def __call__(self, stream):
        return itertools.imap(self._x, stream)

class Filter(Processor, SingleMix):
    __init__ = SingleMix.__init__
    def __call__(self, stream):
        return itertools.ifilter(self._x, stream)

class SplitBy(Processor, SingleMix):
    """split iterables by a element which satisfies the predicate."""
    def __init__(self, predicate):
        SingleMix.__init__(self, predicate)
        self.cont = True
    def __iters(self, iterable):
        for i in iterable:
            if self._x(i):
                return
            yield i
        self.cont = False
    def __call__(self, stream):
        while self.cont:
            yield self.__iters(stream)
        
def iterate(function):
    while True:
        yield function()

#ここまでライブラリ

def iterstream(stream):
    return (SplitBy("\n".__eq__)
            >> Map("".join) >> Map(flip(str.strip)("\r"))
            >> Filter("".__ne__))(iterate(lambda: stream.read(1)))