The Python Oracle

Simpler way to create dictionary of separate variables?

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Chapters
00:00 Simpler Way To Create Dictionary Of Separate Variables?
00:34 Answer 1 Score 14
00:47 Answer 2 Score 131
01:04 Answer 3 Score 17
01:46 Accepted Answer Score 47
01:59 Thank you

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Full question
https://stackoverflow.com/questions/2553...

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Content licensed under CC BY-SA
https://meta.stackexchange.com/help/lice...

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Tags
#python #string #variables

#avk47



ANSWER 1

Score 131


As unwind said, this isn't really something you do in Python - variables are actually name mappings to objects.

However, here's one way to try and do it:

 >>> a = 1
 >>> for k, v in list(locals().iteritems()):
         if v is a:
             a_as_str = k
 >>> a_as_str
 a
 >>> type(a_as_str)
 'str'



ACCEPTED ANSWER

Score 47


Are you trying to do this?

dict( (name,eval(name)) for name in ['some','list','of','vars'] )

Example

>>> some= 1
>>> list= 2
>>> of= 3
>>> vars= 4
>>> dict( (name,eval(name)) for name in ['some','list','of','vars'] )
{'list': 2, 'some': 1, 'vars': 4, 'of': 3}



ANSWER 3

Score 17


This is a hack. It will not work on all Python implementations distributions (in particular, those that do not have traceback.extract_stack.)

import traceback

def make_dict(*expr):
    (filename,line_number,function_name,text)=traceback.extract_stack()[-2]
    begin=text.find('make_dict(')+len('make_dict(')
    end=text.find(')',begin)
    text=[name.strip() for name in text[begin:end].split(',')]
    return dict(zip(text,expr))

bar=True
foo=False
print(make_dict(bar,foo))
# {'foo': False, 'bar': True}

Note that this hack is fragile:

make_dict(bar,
          foo)

(calling make_dict on 2 lines) will not work.

Instead of trying to generate the dict out of the values foo and bar, it would be much more Pythonic to generate the dict out of the string variable names 'foo' and 'bar':

dict([(name,locals()[name]) for name in ('foo','bar')])



ANSWER 4

Score 14


This is not possible in Python, which really doesn't have "variables". Python has names, and there can be more than one name for the same object.