I just want to replace /<form[.*]?*\/form>/ with the word "block"
Well, there's your first huge mistake (apart from the question whether this is a good idea). You're now looking for "<form", followed by any number of occurrences of either "." or "*", and ending in "/form>". Or, it would if you put in your quantifiers in the correct way: 
/<form[.*]*?\/form>/

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It makes sense that it finds nothing.

Where does the idea come from to use square brackets, anyway? Uh, yes, "." is indeed a plain character in a character class. That might be an unexpected pitfall.

So, try again with 

/<form.*?\/form>/s

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The /s is to treat newlines as plain characters in /./s. (You put it after the third slash in s/PAT/REPL/s.)

In reply to Re: How to use a regex to parse html form tags by bart
in thread How to use a regex to parse html form tags by monkeriffic

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