Python3基础 list 查看filter()返回的对象

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• ???????Python : 3.7.0
• ?????????OS : Ubuntu 18.04.1 LTS
• ????????IDE : PyCharm 2018.2.4
• ??????Conda : 4.5.11
• ???typesetting : Markdown

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code

"""
@Author : 行初心
@Date   : 18-9-23
@Blog   : www.cnblogs.com/xingchuxin
@Gitee  : gitee.com/zhichengjiu
"""

def main():
    # 过滤器
    # 通过 过滤器 可以保留自己需要资源

    value = filter(None, [1, -1, 0, True, False, [1, 0, True, False], []])
    value_list = list(value)

    # 有内容的列表被保留了下来，没有内容的列表被删除
    # True被保留，False被删除
    # 0被删除 ，1被保留
    print(value_list)

if __name__ == '__main__':
    main()

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result

/home/coder/anaconda3/envs/py37/bin/python /home/coder/PycharmProjects/DataStructure/demo.py
[1, -1, True, [1, 0, True, False]]

Process finished with exit code 0

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more knowledge

Help on class filter in module builtins:

class filter(object)
 |  filter(function or None, iterable) --> filter object
 |
 |  Return an iterator yielding those items of iterable for which function(item)
 |  is true. If function is None, return the items that are true.
 |
 |  Methods defined here:
 |
 |  __getattribute__(self, name, /)
 |      Return getattr(self, name).
 |
 |  __iter__(self, /)
 |      Implement iter(self).
 |
 |  __next__(self, /)
 |      Implement next(self).
 |
 |  __reduce__(...)
 |      Return state information for pickling.
 |
 |  ----------------------------------------------------------------------
 |  Static methods defined here:
 |
 |  __new__(*args, **kwargs) from builtins.type
 |      Create and return a new object.  See help(type) for accurate signature.

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resource

• [文档] docs.python.org/3
• [规范] www.python.org/dev/peps/pep-0008
• [规范] zh-google-styleguide.readthedocs.io/en/latest/google-python-styleguide/python_language_rules
• [源码] www.python.org/downloads/source
• [ PEP ] www.python.org/dev/peps
• [平台] www.cnblogs.com
• [平台] gitee.com

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原文地址：https://www.cnblogs.com/xingchuxin/p/10440891.html