Printing variable label in function

Question

How would I return a variable name in a function. E.g. If I have the function:

def mul(a,b):
   return a*b

a = mul(1,2); a
b = mul(1,3); b
c = mul(1,4); c

This would return:

2
3
4

I would like it to return:

a = 2
b = 3
c = 4

How would I do this?

If you want to dynamically print out the name: look at this: https://stackoverflow.com/questions/544919/can-i-print-original-variables-name-in-python — MEE, Jan 29 '18 at 18:17
In which function? Your above code is only working in interactive mode. There is no print function called. If you want to create a function `printWithName(x)` that prints the name of x and the value of x look at the above link — MEE, Jan 29 '18 at 18:19
Possible duplicate of [Getting the name of a variable as a string](https://stackoverflow.com/questions/18425225/getting-the-name-of-a-variable-as-a-string) — MEE, Jan 29 '18 at 18:20
`mul` has (and can have, short of introspecting on the code in which it appears) *no* idea what will be done with its return variable, let alone the name of a variable it might be assigned to. — chepner, Jan 29 '18 at 18:24

peachykeen · Answer 1 · 2018-01-29T18:25:34.063

Unfortunately, you are unable to go "backwards" and print the name of a variable. This is explained in much further detail in this StackOverflow post.

What you could do is put the variable names in a dictionary.

dict = {"a":mul(1,2), "b":mul(1,3), "c":mul(1,4)}

From there you could loop through the keys and values and print them out.

for k, v in dict.items():
    print(str(k) + " = " + str(v))

Alternatively, if you wanted your values ordered, you could put the values into a list of tuples and again loop through them in a for loop.

lst = [("a", mul(1,2)), ("b", mul(1,3)), ("c",mul(1,4))]

score 0 · Answer 2 · answered Jul 09 '20 at 20:11

Here is how to do it with python-varname package:

from varname import varname

def mul(a, b):
   var = varname()
   return f"{var} = {a*b}"

a = mul(1,2)
b = mul(1,3)
c = mul(1,4)

print(a) # 'a = 2'
print(b) # 'b = 2'
print(c) # 'c = 2'

The package is hosted at https://github.com/pwwang/python-varname.

I am the author of the package. Let me know if you have any questions using it.

Printing variable label in function

2 Answers2