求匹配固定有序单词序列的Regex表达式（可含数字分隔）

Example for Two Words (my_word followed by my_other_word) #

The regex below matches all your sample cases while enforcing the fixed order of words and allowing numeric segments between/after words:

^my_word(?:\.\d+)*(?:\.my_other_word(?:\.\d+)*)?$

Breakdown: #

• ^my_word: Starts with the exact first word my_word
• (?:\.\d+)*: Optional repeated sequence of a dot followed by one or more digits (matches numeric segments after my_word)
• (?:\.my_other_word(?:\.\d+)*)?: Optional sequence that:
  • Starts with a dot followed by the exact second word my_other_word
  • Followed by optional repeated numeric segments (dot + digits)
• $: Ensures the string ends here (no extra characters after the last segment)

Valid Matches (Your Samples): #

• my_word
• my_word.0
• my_word.1
• my_word.0.my_other_word
• my_word.my_other_word
• my_word.my_other_word.0

Generalizing to Any Number of Ordered Words #

If you have a list of words in fixed order (e.g., W1, W2, W3, ..., Wn), the pattern follows this reusable structure:

^W1(?:\.\d+)*(?:\.W2(?:\.\d+)*(?:\.W3(?:\.\d+)*)*...(?:\.Wn(?:\.\d+)*)?)?$

Build Steps: #

1. Start with ^W1 (anchor the first word at the string start)
2. Add (?:\.\d+)* to allow any number of numeric segments after the first word
3. For each subsequent word Wk:
   • Wrap it in (?:\.Wk(?:\.\d+)*) to require the word in order, followed by optional numeric segments
   • Make each sequence optional (add ? at the end) to allow stopping at any previous word in the list
4. End with $ to match the full string (no extra trailing characters)

Example for Three Words (W1, W2, W3) #

^W1(?:\.\d+)*(?:\.W2(?:\.\d+)*(?:\.W3(?:\.\d+)*)?)?$

This pattern will match cases like:

• W1
• W1.123
• W1.W2
• W1.456.W2.789
• W1.W2.W3
• W1.0.W2.W3.9

内容的提问来源于stack exchange，提问作者Brendan