range()——python2与pyt
当你在不同python版本下使用 range() 时， 需要注意了
我们先在原始IDE下分别码出来：
python 2.
>>> range(2, 19)
[2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18]python 3.
>>> range(2, 19)
range(2, 19)而这样
>>> list(range(2, 19))
[2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18]为什么会这样呢？
这是因为，在py2中range()是作为内置函数， 而在py3中是作为一个内置的方法
注意看以下的源代码（部分）：
py2
def range(start=None, stop=None, step=None): # known special case of range
"""
range(stop) -> list of integers
range(start, stop[, step]) -> list of integers
Return a list containing an arithmetic progression of integers.
range(i, j) returns [i, i+1, i+2, ..., j-1]; start (!) defaults to 0.
When step is given, it specifies the increment (or decrement).
For example, range(4) returns [0, 1, 2, 3]. The end point is omitted!
These are exactly the valid indices for a list of 4 elements.
"""
passpy3
class range(object):
"""
range(stop) -> range object
range(start, stop[, step]) -> range object
Return an object that produces a sequence of integers from start (inclusive)
to stop (exclusive) by step. range(i, j) produces i, i+1, i+2, ..., j-1.
start defaults to 0, and stop is omitted! range(4) produces 0, 1, 2, 3.
These are exactly the valid indices for a list of 4 elements.
When step is given, it specifies the increment (or decrement).
"""运行环境分别为2.7.14和3.5.4
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原始发表：2019/09/27 ，如有侵权请联系 cloudcommunity@tencent.com 删除
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