Python正则表达式用不同的括号分割字符串

Question

I have a string that could look like:

"set<array<char, [100:140, 40:80]>>"

or

"set<array<struct{int foo, char bar}, [100:150, 50:80]>>"

basically the structure within the "array" could be either a primitive or a struct of primitives, or a struct of structs.

Using python regex module, I want to get a return something like this object:

{"base_type":"array", "type":"char"}

or, for second one:

{"base_type":"array", "type":"struct", "sub_type":["int", "char"]}

Maybe there's a more elegant way to do this without using regular expressions. Any help would be really appreciated. :)

Answer 1

According to these two test cases you provided, I come up with two regex expressions:

1. "set<array<(char|float|int), .*>>" for these cases with primary types nested.
2. "set<array<struct{((int|char|float)\\s+.*,)*\\s+((int|char|float) .*)}, .*>>" for these cases with struct type nested.

You can use group to find out what primary types are nested and what types are in the struct.

Here is my solution in python:

# -*- coding: utf-8 -*-
import re

primary_regex = "set<array<(char|float|int), .*>>"
struct_regex = (
    "set<array<struct{((int|char|float)\s+.*,)*\s+((int|char|float) .*)}, .*>>"
)


def extract(define_str):
    m = re.match(primary_regex, define_str)
    result = {
        'base_type': 'array',
    }

    if m is None:
        m = re.match(struct_regex, define_str)

        if m is None:
            # Invalid define_str, return None
            return None

        # Result of m.groups() is a tuple alike
        # ('int foo,', 'int', 'char bar', 'char')
        sub_type = m.groups()[1::2]
        result['type'] = 'struct'
        result['sub_type'] = sub_type
    else:
        primary_type = m.group(1)
        result['type'] = primary_type

    return result

Hope this will help.