python - 如何检查 str int 列表和元组？

Question

有一个文件包括 str int 列表和元组。我想把它们放在不同的列表中。

这是我的示例代码：

for word in file:
    if type(word) == int:
        ......
    if type(word) == list:
        ......

我可以检查 int 使用 type(word) == int

但我不能在我的代码中使用 'type(word) == list'。

那么，如何检查文件是“列表”还是“元组”？

Answer 1

这应该工作 -

for word in file:
    if isinstance(word, int):
        ...
    elif isinstance(word, list):
        ...
    elif isinstance(word, tuple):
        ...
    elif isinstance(word, str):
        ...

Answer 2

如果没有可以利用的模式来预测文件的每一行将代表什么，那么您可以提前尝试这个快速而肮脏的解决方案：

for word in file:
    # Read the word as the appropriate type (int, str, list, etc.)
    try:
        word = eval(word) # will be as though you pasted the line from the file directly into the Python file (e.g. "word = 342.54" if word is the string "342.54").  Works for lists and tuples as well.
    except:
        pass # word remains as the String that was read from the file

    # Find what type it is and do whatever you're doing
    if type(word) == int:
        # add to list of ints
    elif type(word) == list:
        # add to list of lists
    elif type(word) == tuple:
        # add to list of tuples
    elif type(word) == str:
        # add to list of strs

Answer 3

你可以使用类型

from types import *
type(word) == ListType
type(word) == TupleType

作为您的问题，您可以简单地编码为：

>>> from types import *
>>> file = [1,"aa",3,'d',[23,1],(12,34)]
>>> int_list = [item for item in file if type(item)==int]
>>> int_list
[1, 3]