Python - 如何将此模式(数字/数字)与正则表达式匹配？

Question

我试图了解python中的正则表达式模块。我试图让我的程序从用户输入的一行文本中匹配以下模式:
8-13 之间的数字“/” 0-15 之间的数字
例如:8/2、11/13、10/9 等。
我想出的模式是:upstream = re.compile(r'[8-9|1[0-3][/][0-9|1[0-5]')然而，这个正则表达式的工作结果好坏参半:

Enter a slot/port : 8/2    
['8/2']                    # This is correct

Enter a slot/port : 1/0    
['1/0']                    # This should print the "else" statement

Enter a slot/port : 8/15
['8/1']                    # The output is incomplete

问题似乎源于正斜杠，但我不确定。我知道我需要一些帮助来解决这个问题。如果有人能帮我解决这个问题，我将不胜感激。
完整的脚本如下。

import re
pattern = re.compile(r'[8-9|1[0-3][/][0-9|1[0-5]')

upstream = input("Enter a slot/port : ")

if re.search((pattern), upstream):
    print(re.findall(pattern, upstream))
else:
    print("We have a problem")

提前致谢 :)

Answer 1

您的表达式格式不正确，因为您在必须使用圆括号的地方使用了方括号。 [8-9|1[0-3]和 [0-9|1[0-5]两者都是错误的模式，如 [8-9和 [0-9不是封闭的字符类。
采用

\b(?:[89]|1[0-3])/(?:[0-9]|1[0-5])\b

见 regex proof .
解释

--------------------------------------------------------------------------------
  \b                       the boundary between a word char (\w) and
                           something that is not a word char
--------------------------------------------------------------------------------
  (?:                      group, but do not capture:
--------------------------------------------------------------------------------
    [89]                     any character of: '8', '9'
--------------------------------------------------------------------------------
   |                        OR
--------------------------------------------------------------------------------
    1                        '1'
--------------------------------------------------------------------------------
    [0-3]                    any character of: '0' to '3'
--------------------------------------------------------------------------------
  )                        end of grouping
--------------------------------------------------------------------------------
  /                        '/'
--------------------------------------------------------------------------------
  (?:                      group, but do not capture:
--------------------------------------------------------------------------------
    [0-9]                    any character of: '0' to '9'
--------------------------------------------------------------------------------
   |                        OR
--------------------------------------------------------------------------------
    1                        '1'
--------------------------------------------------------------------------------
    [0-5]                    any character of: '0' to '5'
--------------------------------------------------------------------------------
  )                        end of grouping
--------------------------------------------------------------------------------
  \b                       the boundary between a word char (\w) and
                           something that is not a word char