4ppl3c0r3 Thanks for your input. I am more familiar with unix regular expressions. They have a lot in common. I cannot see why this statement has a hit:
echo "a=autodiscover xxx b=powershell" | Select-String -Pattern "(?=.*autodiscover)(?=.*powershell)"The ( and ) only groups thing, The "=" is a literal "=". So it should not find it.
But as you say "if you find the word "autodiscover" and the word "powershell," in either order" this also gives a hit. So I understand probably not some fundamentals of -pattern. I have read the documentation though.
echo "b=powershell a=autodiscover" | Select-String -Pattern "(?=.*autodiscover)(?=.*powershell)"I understand the ^and $ for going into Singleline mode.
I do not understand why you added:
(?:.*)Aha now I found it. The ? is not "match any character" if it is in between ( and ). It means:
(? = Balancing Group Definition
and
(?:.*) = Noncapturing Groups. The following grouping construct does not capture the substring that is matched by a subexpression: (?:subexpression)