Change variable name using a function

Question

I want to make a variable with help of a function that gets its name from an argument, so that if I run this;

hi_var(abc)
print(abc)

I will get hi as output

I currently have this, but it is completely not working;

def hi_var(var_name):
  text = "hi"
  return text as var_name

It would be great if someone knew how to do this

This is not possible in Python, in general. It also isn't really desirable or necessary. — juanpa.arrivillaga, Dec 28 '20 at 09:25
Does this answer your question? [generating variable names on fly in python](https://stackoverflow.com/questions/4010840/generating-variable-names-on-fly-in-python) — rfkortekaas, Dec 28 '20 at 09:30
It's not entirely clear what you are trying to do. Do you want ``hi_var(abc)`` to be equivalent to ``abc = "hi"``? What do you expect to happen when ``hi_var`` is used in a class or function scope, or in another expression – which namespace should the variable be set in? Is there any reason why you do not just use the equivalent assignment statement or expression? — MisterMiyagi, Dec 28 '20 at 09:52

score 0 · Accepted Answer · answered Dec 28 '20 at 09:32

0

I am not sure why you want to do this, but if you like you can access the global variable directory and add the variable there:

def hi_var(var_name):
    text = 'hi'
    globals()[var_name] = text

hi_var('abc')
print(abc)

answered Dec 28 '20 at 09:32

Querenker

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Sheena · Answer 2 · 2020-12-28T12:21:03.240

0

@Querenker's solution will work, but generally speaking it's not great to use global variables. It gets a bit messy. Also unit testing can get tricky.

I think it would be better to store everything somewhere specific.

eg:

dynamic_goodies = {}

def hi_var(var_name):
  text = "hi"
  dynamic_goodies[var_name] = text
  return text

hi_var(`abc`)
print(dynamic_goodies['abc'])

If this doesn't solve it for you can you add a little more info to your question? Why do you want to do this thing?

edited Dec 28 '20 at 12:21

answered Dec 28 '20 at 10:06

Sheena

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``locals`` at global scope *is* ``globals``. In recent Python versions, changes to function``locals`` do not actually change values of variables. – MisterMiyagi Dec 28 '20 at 10:08
@MisterMiyagi thanks, I learned something from your comment – Sheena Dec 28 '20 at 12:21

Anaam · Answer 3 · 2020-12-28T11:07:43.203

0

In python, module variables which includes the REPL gets stored in a dictionary called globals(). Typing globals() into the console will show the dictionary.

Although, the question being not so clear to me, as far I understood you needed a function that can assign values to variables. So, here's an example of such a function.

def cv(var_name, value='hi'): 
    """
    create varibles
    """
    globals()[var_name] = value

cv('h')
print(h)

Output:

hi

edited Dec 28 '20 at 11:07

answered Dec 28 '20 at 10:28

Anaam

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Variables are *not* all stored in the ``globals`` dictionary. Only module variables, which includes the REPL, are stored in ``globals``. Python knows *at least* three other kinds of variables, namely (function) local, closure and class. – MisterMiyagi Dec 28 '20 at 10:33

Change variable name using a function

3 Answers3