Question

Referring on this question, I have a similar -but not the same- problem..

On my way, I’ll have some text file, structured like:

var_a: 'home'
var_b: 'car'
var_c: 15.5

And I need that python read the file and then create a variable named var_a with value ‘home’, and so on.

Example:

#python stuff over here
getVarFromFile(filename) #this is the function that im looking for
print var_b
#output: car, as string
print var_c
#output 15.5, as number.

Is this possible, I mean, even keep the var type?

Notice that I have the full freedom to the text file structure, I can use the format I like if the one I proposed isn’t the best.

EDIT: the ConfigParser can be a solution, but I don’t like it so much, because in my script I’ll have then to refer to the variables in the file with

config.get("set", "var_name")

But what I’ll love is to refer to the variable directly, as I declared it in the python script…

There is a way to import the file as a python dictionary?

Oh, last thing, keep in mind that I don’t know exactly how many variables would I have in the text file.

Edit 2: I’m very interested at stephan’s JSON solution, because in that way the text file could be read simply with others languages (PHP, then via AJAX JavaScript, for example), but I fail in something while acting that solution:

#for the example, i dont load the file but create a var with the supposed file content
file_content = "'var_a': 4, 'var_b': 'a string'"
mydict = dict(file_content)
#Error: ValueError: dictionary update sequence element #0 has length 1; 2 is required
file_content_2 = "{'var_a': 4, 'var_b': 'a string'}"
mydict_2 = dict(json.dump(file_content_2, True))
#Error:
#Traceback (most recent call last):
#File "<pyshell#5>", line 1, in <module>
#mydict_2 = dict(json.dump(file_content_2, True))
#File "C:\Python26\lib\json\__init__.py", line 181, in dump
#fp.write(chunk)
#AttributeError: 'bool' object has no attribute 'write'

In what kind of issues can I fall with the JSON format?
And, how can I read a JSON array in a text file, and transform it in a python dict?

P.S: I don’t like the solution using .py files; I’ll prefer .txt, .inc, .whatever is not restrictive to one language.

Answer 1

Load your file with JSON or PyYAML into a dictionary the_dict (see doc for JSON or PyYAML for this step, both can store data type) and add the dictionary to your globals dictionary, e.g. using globals().update(the_dict).

If you want it in a local dictionary instead (e.g. inside a function), you can do it like this:

for (n, v) in the_dict.items():
    exec('%s=%s' % (n, repr(v)))

as long as it is safe to use exec. If not, you can use the dictionary directly.