XSLT内の正規表現

Question

XSLTの通常のエクスクションの下でこれを理解するのに誰かが助けてくれますか？

regexp:match(test-graph.api.example.com, '(?=CN).*\.(.*)(\.)(.*)(?<=com)', 'i') 

この正規表現の出力とその解釈方法は何でしょうか。

私は

Answer 1

を教えてくださいこのように読まれるべきです。

(?=CN).*\.(.*)(\.)(.*)(?<=com) 

説明：

.* matches any character (except for line terminators) 
    * Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy) 
\. matches the character . literally (case sensitive) 
1st Capturing Group (.*) 
.* matches any character (except for line terminators) 
    * Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy) 
2nd Capturing Group (\.) 
\. matches the character . literally 
3rd Capturing Group (.*) 
.* matches any character (except for line terminators) 
    * Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy) 
Positive Lookbehind (?<=com) 
Assert that the Regex below matches 
com matches the characters com literally 

i修飾子は正規表現がケース私は nsentiveであることを意味します。