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aaronmk
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# Iterators and iterables
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aaronmk
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aaronmk
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import rand
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aaronmk
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def is_iterable(value): return getattr(value, '__iter__', False)
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aaronmk
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# Sentinel to use in iter() if function return value should be ignored.
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# Can't use object() because iter() compares sentinel using ==.
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iter_end = rand.rand_int()
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1892
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aaronmk
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def func_iter(func):
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'''Used to iterate a generating function which raises StopIteration instead
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of returning a sentinel value'''
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return iter(func, iter_end)
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def consume_iter(iter_):
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for elem in iter_: pass
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aaronmk
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def flatten(outer_iter):
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if is_iterable(outer_iter):
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for iter_ in outer_iter:
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if is_iterable(iter_):
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for el in iter_: yield el
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else: yield iter_
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else: yield outer_iter
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aaronmk
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def flatten_n(outer_iter, depth=2):
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if depth < 2: return outer_iter
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elif depth == 2: return flatten(outer_iter)
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else: return flatten(flatten_n(outer_iter, depth-1))
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