munges a string so that it is a valid matlab variable name

matlab_sanitizer.py

import re

def known_bad(x):
    """provide string substitutions for common invalid tokens, or remove them if not found."""
    return {' ': '_',
            '(': '_lp_',
            ')': '_rp_',
            '-': '_minus_',
            '/': '_div_',
            ';': '_sc_'
            }.get(x, '')


def sanitize_name(namestr):
    """A valid variable name starts with a letter, followed by letters, 
    digits, or underscores, and cannot be one of several reserved words."""
    keywords = {'break', 'case', 'catch', 'classdef', 'continue', 'else', 'elseif', 'end', 'for', 'function',
                'global', 'if', 'otherwise', 'parfor', 'persistent', 'return', 'spmd', 'switch', 'try', 'while'}
    if namestr in keywords:
        raise NameError(f'{namestr} is not a valid matlab name')    
    
    # match whatever isn't alphanumeric or underscore
    for illegal in re.compile(r'([^A-Za-z0-9_])').findall(namestr):
        namestr = namestr.replace(illegal, known_bad(illegal))
    if not namestr[0].isalpha():
        namestr = f'm_{namestr}'
    return namestr