Fri Jan 6 02:52:13 EST 2006
rurpy at yahoo.com writes:
> def izip4(*iterables, **kw):
> """kw:fill. An element that will pad the shorter iterable
> kw:infinite. Number of non-terminating iterators """
That's a really kludgy API. I'm not sure what to propose instead:
maybe some way of distinguishing which iterables are supposed to be
iterated til exhaustion (untested):
class Discardable(object): pass
def izip5(*iterables, fill=None):
"""Run until all non-discardable iterators are exhausted"""
# exhausted iterables will put empty tuples into t
# non-exhausted iterables will put singleton tuples there
t = [tuple(islice(i,1)) for i in iterables]
# quit if only discardables are left
dropwhile(lambda i,t: (not isinstance(i, Discardable)) and len(t)),
yield tuple([(v if len(t) else fill) for v in t])
Then you'd wrap "infinite" and other iterators you don't need exhausted
stream = izip5(a, b, Discardable(c), d, Discardable(e), fill='')
runs until a, b, and d are all exhausted.
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