checkpoint

mahmoud · moshez · Dec 10, 2022 · Dec 12, 2022 · Dec 12, 2022 · Dec 12, 2022
commit b508d1c79a20fcbf8b9eedd3352d3ac2b407737a
diff --git a/boltons/iterutils.py b/boltons/iterutils.py
@@ -1524,6 +1524,51 @@ def _iter_or_num(thing: Union[Iterable[float], float]) -> Iterator[float]:
 
 @dataclasses.dataclass
 class NumIterator:
+
+ """An iterator of numbers.
+
+ Supports math operations and slicing.
+
+ >>> list(NumIterator(range(3)))
+ [0, 1, 2]
+ >>> list(NumIterator(range(3)) + 1)
+ [1, 2, 3]
+ >>> list(NumIterator(range(3)) * 2)
+ [0, 2, 4]
+ >>> list(NumIterator(x + 1 for x in range(10))[:3])
+ [1, 2, 3]
+
+ There are also a few helper class methods to generate
+ common iterators.
+ They all generate *infinite* iterators.
+ Convert them to finite iterators using slicing.
+
+ Counting:
+
+ >>> list(NumIterator.count()[:5])
+ [0, 1, 2, 3, 4]
+
+ Constant:
+
+ >>> list(NumIterator.constant(7)[:2])
+ [7, 7]
+
+ Fibonacci sequence:
+
+ >>> list(NumIterator.fib()[:8])
+ [0, 1, 1, 2, 3, 5, 8, 13]
+
+ Since the iterators support math operations,
+ you can combine them to generate more sophisticated
+ sequences.
+
+ For example,
+
+ >>> fib_pow_of_2 = 2 ** NumIterator.count() + NumIterator.fib()
+ >>> list(fib_pow_of_2[:5])
+ [1, 3, 5, 10, 19]
+ """
+
  _original: Iterable[float]
 
  @classmethod