How to non-greedy multiple lookbehind matches

regex lookbehind non-greedy
ArtK picture ArtK · Aug 5, 2009 · Viewed 7.8k times · Source 
Source:    <prefix><content1><suffix1><prefix><content2><suffix2>
Engine:    PCRE

RegEx1:    (?<=<prefix>)(.*)(?=<suffix1>)
RegEx2:    (?<=<prefix>)(.*)(?=<suffix2>)

Result1:   <content1>
Result2:   <content1><suffix1><prefix><content2>

The desired result for RegEx2 is just <content2> but it is obviously greedy. How do I make RegEx2 non-greedy and use only the last matching lookbehind?

[I hope I have translated this correctly from the NoteTab syntax. I don't do much RegEx coding. The <prefix>, <content> & <suffix> terms are just meant to represent arbitrary strings. Only the "<" in the "?<=" lookbehind command is significant.]

I suspect it is something simple but after too many hours of searching I'm giving up on solving it myself.

Thanks for the help

Art

Answer

Tim Pietzcker picture Tim Pietzcker · Aug 5, 2009

I suggest you use:

(?<=<prefix>)(((?!<prefix>).)*)(?=<suffix2>)

This makes sure that there can be no <prefix> inside the match. The complete match result will be <content2>

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