在函数中打印变量标签

Question

How would I return a variable name in a function. Eg 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?

Answer 1

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))]

Answer 2

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.