复杂条件正则表达式分组

Question

我有以下文字：

 1. The SBI considered this sub-item at its resumed 1^st^ meeting and at its 2^nd^ meeting (see
    para. 46 above). It had before it documents FCCC/CP/2011/7 and Corr.1 and Add.1 and 2, 
    FCCC/SBI/2010/17, FCCC/SBI/2010/26 and FCCC/SBI/2010/MISC.9. A statement was made on behalf of the LDCs.

我对提取遵循以下模式的文档名称感兴趣：(FCCC\/(?:SBSTA|SBI|CP|KP\/CMP|PA\/CMA)\/[0-9]{4}\/(?:INF\.|L\.|MISC\.)?[0-9]+(?:\/Add\.[0-9])?(?:\/Rev\.[0-9]+)?) 这是 FCCC/Document_type(SBSTA or SBI, etc.)/Year/Number，它们可能有也可能没有添加、更正和修订。

有两种方法可以引用添加或修订：

在名称末尾添加：添加 /Rev 或 /Add + 数字
或and Rev|Add|Corr .num

然后根据我感兴趣的文本构建第二个选项引用的名称。例如，映射：FCCC/CP/2011/7 and Corr.1 and Add.1 and 2 到 ["FCCC/CP/2011/7", "FCCC/CP/2011/7/Corr.1", "FCCC/CP/2011/7/Add.1", "FCCC/CP/2011/7/Add.2"].

这是我目前的做法：

def _find_documents(par: str) -> Union[list, None]:
    """
    Finds referenced documents
    :param par:
    :return:
    """
    found_list = []
    pattern = r"(FCCC\/(?:SBSTA|SBI|CP|KP\/CMP|PA\/CMA)\/[0-9]{4}\/(?:INF\.|L\.|MISC\.)?[0-9]+(?:\/Add\.[0-9])?(?:\/Rev\.[0-9]+)?)"
    found = re.findall(pattern, par)

    # Now, we look for corrections and Revisions
    for doc in found:
        found_list.append(doc)
        doc = doc.replace(r"/", r"\/")
        pattern = doc + r"(?: and ((:?Corr\.|Add\.)?[0-9]))?(?: and ((:?Corr\.|Add\.)[0-9]))*(:? and ([0-9])+)?"
        res = re.search(pattern, par).groups()
        for pat in res:
            if pat is not None:
                found_list.append(doc + "/" + pat)

    return found_list if found_list is not None else None

    st = r"""
    50. The SBI considered this sub-item at its resumed 1^st^ meeting and at its 2^nd^ meeting (see para. 46 above). It had before it documents FCCC/CP/2011/7 and Corr.1 and Add.1 and 2, FCCC/SBI/2010/17, FCCC/SBI/2010/26 and FCCC/SBI/2010/MISC.9. A statement was made on behalf of the LDCs.
    """
    
    _find_documents(st)
    """ [OUT]: 
    ['FCCC/CP/2011/7',
     'FCCC\/CP\/2011\/7/Corr.1',
    'FCCC\/CP\/2011\/7/Corr.',  EXTRA
    'FCCC\/CP\/2011\/7/Add.1',
    'FCCC\/CP\/2011\/7/Add.',  EXTRA
    'FCCC\/CP\/2011\/7/ and 2',  EXTRA
    'FCCC\/CP\/2011\/7/2', WRONG Should be FCCC/CP/2011/7/Add.2
    'FCCC/SBI/2010/17',
    'FCCC/SBI/2010/26',
    'FCCC/SBI/2010/MISC.9']"""

如您所见，我有几个问题不知道如何解决。

小组获得额外比赛["Add.", "Corr.", "and 2"]
当我尝试附加 Corrs、Apps 时，/ 以某种方式被转义。
不确定如何将子匹配 and 2 映射到 /Add.2 或 /Corr.2，具体取决于之前的

有什么想法吗？

谢谢，

Answer 1

你可以使用

import re
text = "50. The SBI considered this sub-item at its resumed 1^st^ meeting and at its 2^nd^ meeting (see para. 46 above). It had before it documents FCCC/CP/2011/7 and Corr.1 and Add.1 and 2, FCCC/SBI/2010/17, FCCC/SBI/2010/26 and FCCC/SBI/2010/MISC.9. A statement was made on behalf of the LDCs."
rx_main = re.compile(r'(FCCC/(?:SBSTA|SBI|CP|KP/CMP|PA/CMA)/\d{4}/(?:INF\.|L\.|MISC\.)?\d+)((?:(?:/|\s+and\s+|\s*,\s*)(?:Add|Rev|Corr)\.\d+(?:(?:\s*,\s*|\s+and\s+)\d+)*)*)')
rx_rev = re.compile(r'(?:Add|Rev|Corr)\.\d+(?:(?:\s*,\s*|\s+and\s+)\d+)*')
rx_split = re.compile(r'\s*,\s*|\s+and\s+')
matches = rx_main.finditer(text)
results = []
for m in matches:
    results.append(m.group(1))
    chunks = [rx_split.split(x) for x in rx_rev.findall(m.group(2))]
    for ch in chunks:
        if len(ch) == 1: # it is simple, just add first item to Group 1
            results.append(f"{m.group(1)}/{ch[0]}")
        else:
            name = ch[0].split('.')[0] # Rev, Corr or Add
            for c in ch:
                if '.' in c: # if there is a dot, append whole string to Group 1
                    results.append(f"{m.group(1)}/{c}")
                else:
                    results.append(f"{m.group(1)}/{name}.{c}") # Append the new number to Corr/Add/Rev

print(results)

输出：

['FCCC/CP/2011/7', 'FCCC/CP/2011/7/Corr.1', 'FCCC/CP/2011/7/Add.1', 'FCCC/CP/2011/7/Add.2', 'FCCC/SBI/2010/17', 'FCCC/SBI/2010/26', 'FCCC/SBI/2010/MISC.9']

参见 this Python demo。

新的正则表达式是

(FCCC/(?:SBSTA|SBI|CP|KP/CMP|PA/CMA)/\d{4}/(?:INF\.|L\.|MISC\.)?\d+)((?:(?:/|\s+and\s+|\s*,\s*)(?:Add|Rev|Corr)\.\d+(?:(?:\s*,\s*|\s+and\s+)\d+)*)*)

参见regex demo。

复杂条件正则表达式分组

Complex conditional Regex grouping

python

regex

escaping