I will be processing large amounts of HTML, and I want to find and replace any ampersands that are not part of an existing html entity with their own & entity. From some pre-existing code, I have a regular expression for finding entities of (I think) all possible kinds: 
m/(&(?:(?:#x[\da-f]+)|(?:#\d+)|(?:[a-z]+));)/i

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However, I'm struggling with how to find and replace all ampersands that would not match the previous expression...I know what I want to do, but am wrestling with the logic of how to do it. Can anyone offer suggestions?

For example, the following would be before processing: 

Purus Accumsan Felis ‰ Maecenas Nibh θ Eget Phasellus & Mi
+ Amet.  Odio Amet && Purus.  Mi Ullamcorper Lorem Eget Nibh.

http://www.example.com/?name=John&residence=Vatican+City&job=Pope

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And this would be after processing: 
Purus Accumsan Felis ‰ Maecenas Nibh θ Eget Phasellus &amp
+; Mi Amet.  Odio Amet && Purus.  Mi Ullamcorper Lorem Eget Ni
+bh.

http://www.example.com/?name=John&residence=Vatican+City&job=P
+ope

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In reply to Matching ampersands that are NOT part of an HTML entity? by Anonymous Monk

Title:
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