How Can I Get a Python Variable\'s Name at Runtime?

Intercepting Variable Names in Python

In Python, accessing a variable's name directly is not a straightforward task. However, for specific scenarios, where obtaining the variable name is crucial, consider the following solution.

The Inspect Module Trickery

Through the inspect module, you can traverse the call stack and extract the variable name of interest. Here's how it's done:

import inspect, re

def varname(p):
  for line in inspect.getframeinfo(inspect.currentframe().f_back)[3]:
    m = re.search(r'\bvarname\s*\(\s*([A-Za-z_][A-Za-z0-9_]*)\s*\)', line)
    if m:
      return m.group(1)

Usage Example

To illustrate its functionality, suppose you have a variable named spam with a value of 42. Using the varname() function, you can retrieve its name:

if __name__ == '__main__':
  spam = 42
  print varname(spam)

Output

The output will be:

spam

Note of Caution

While this approach provides a means to access variable names, it's important to use it judiciously. Direct variable naming is generally discouraged in Pythonic coding practices. Consider alternative solutions, such as transforming the configuration file into a dictionary during initialization to avoid the need for this technique.

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