How Can I Determine the Name of a Python Variable Programmatically?

Determining Variable Names in Python

When working with variables in Python, it can sometimes be necessary to access their names. While Python does not provide a direct function to obtain variable names, one approach involves introspection.

Inspecting the current stack frame using inspect.getframeinfo(inspect.currentframe().f_back) provides access to the source code lines. Within each line, a regular expression can be used to search for calls to a function that takes a variable as an argument. The function name, which is likely varname, can be used to identify the line that defines the variable. By extracting the variable name from that line using a regular expression, the desired result is obtained.

Here's an example of such an implementation:

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)

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

This inspect-based solution should be considered carefully as it may lead to unexpected behavior in certain situations. Therefore, alternative approaches, such as reading a configuration file and generating a dictionary, should be explored.

The above is the detailed content of How Can I Determine the Name of a Python Variable Programmatically?. For more information, please follow other related articles on the PHP Chinese website!