Regular expression to match function name and all arguments in Python

Question

Suppose I have a string such as the following:

\"func(arg1, arg2, arg3, arg4, ..., argn)\"

EDIT: This function is not in some particular la

Answer 1

Looks like you're 90% there, why not just swap the arg and args groupings and do:

import re

fn_match = re.match(r"(?P<function>\w+)\s?\((?P<arg>(?P<args>\w+(,\s?)?)+)\)", s)
fn_dict = fn_match.groupdict()
del fn_dict['args']
fn_dict['arg'] = [arg.strip() for arg in fn_dict['arg'].split(',')]

Answer 2

To answer the last part of your question: No. Python does not have anything similar to Scheme's "match", nor does it have pattern matching like ML/Haskell. The closest thing it has is the ability to destructure things like this

>>> (a, [b, c, (d, e)]) = (1, [9, 4, (45, 8)])
>>> e
8

And to extract the head and tail of a list (in Python 3.x) like this...

>>> head, *tail = [1,2,3,4,5]
>>> tail
[2, 3, 4, 5]

There are some modules floating around that do real pattern matching in python though, but I can't vouch for their quality.

If I had to do it, I would implement it a bit differently -- maybe have the ability to input a type and optional arguments (e.g. length, or exact content) and a function to call if it matches, so like match([list, length=3, check=(3, str), func]) and that would match (list _ _ somestr) and call func with somestr in scope, and you could also add more patterns.

Answer 3

Regular expressions cannot parse complex programming languages.

If you're just trying to parse Python, I suggest taking a look at the ast module, which will parse it for you.