Lua pattern help (Double parentheses)

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I have been coding a program in Lua that automatically formats IRC logs from a roleplay. In the roleplay logs there is a specific guideline for "Out of character" conversation, which we use double parentheses for. For example: ((<Things unrelated to roleplay go here>)). I have been trying to have my program remove text between double brackets (and including both brackets). The code is:

ofile = io.open("Output.txt", "w")
rfile = io.open("Input.txt", "r")
p = rfile:read("*all")
w = string.gsub(p, "%(%(.*?%)%)", "")
ofile:write(w)

The pattern here is > "%(%(.*?%)%)" I've tried multiple variations of the pattern. All resulted in fruitless results:

1. %(%(.*?%)%) --Wouldn't do anything.
2. %(%(.*%)%) --Would remove *everything* after the first OOC message.

Then, my friend told me that prepending the brackets with percentages wouldn't work, and that I had to use backslashes to 'escape' the parentheses.

3. \(\(.*\)\) --resulted in the output file being completely empty.
4. (\(\(.*\)\)) --Same result as above.
5. (\(\(.*?\)\) --would for some reason, remove large parts of the text for no apparent reason.
6. \(\(.*?\)\) --would just remove all the text except for the last line.

The short, absolute question: What pattern would I need to use to remove all text between double parentheses, and remove the double parentheses themselves too?

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Colonel Thirty Two On BEST ANSWER

You're friend is thinking of regular expressions. Lua patterns are similar, but different. % is the correct escape character.

Your pattern should be %(%(.-%)%). The - is similar to * in that it matches any number of the preceding sequence, but while * tries to match as many characters as it can (it's greedy), - matches the least amount of characters possible (it's non-greedy). It won't go overboard and match extra double-close-parenthesis.