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How to convert string representation of list to a list (21 answers)

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>>> import ast
>>> string =  [Small, Medium, Large, X-Large] 
>>> print string
[Small, Medium, Large, X-Large]
>>> string = ast.literal_eval(string)
Traceback (most recent call last):  
    File "<pyshell#26>", line 1, in <module>
         string = ast.literal_eval(string)
    File "C:Python27libast.py", line 80, in literal_eval
        return _convert(node_or_string)
    File "C:Python27libast.py", line 60, in _convert
        return list(map(_convert, node.elts))
  File "C:Python27libast.py", line 79, in _convert
    raise ValueError( malformed string )
ValueError: malformed string

如何确定?

Answer 1

ast.literal_eval( 只接受含有有效字面结构的体体(体积、编号、标记、清单、标语、ole、和<代码>None)。

这是一种有效的陈词,只包含这些字面结构:

["Small", "Medium", "Large", "X-Large"]

:

[Small, Medium, Large, X-Large]

3. 创建一种行之有效的方法:

string =  ["Small", "Medium", "Large", "X-Large"] 
string = "[ Small ,  Medium ,  Large ,  X-Large ]"

Answer 2

你的扼杀没有一份有效的清单。如果有的话,你需要引述。

E.g:

string =  ["Small", "Medium", "Large", "X-Large"]

Answer 3

If your have many not-quoted strings inside your sting list, you can do this:

string =  [Small, Medium, Large, X-Large] 

[s.strip() for s in string[1:-1].split( , )]

原文照发:

[ Small ,  Medium ,  Large ,  X-Large ]

但是,如果您在座标和上有号>,则您可使用<代码>eval及其globals参数:

mixed_string =  [1, +2, X,0  , - 4, XX, 11.2] 

eval(mixed_string, { X :  X ,  XX :  XX })

原文照发:

[1, 2,  X , 0, -4,  XX , 11.2]

1. 将所有清单项目作为计票:

[str(s) for s in eval(mixed_string, { X :  X ,  XX :  XX })]

原文照发:

[ 1 ,  2 ,  X ,  0 ,  -4 ,  XX ,  11.2 ]

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