TweetShorten.lua

local Message = "This is a very powerful function and can be used in multiple ways. Used simply it can replace all instances of the pattern provided with the replacement. A pair of values is returned, the modified string and the number of substitutions made. The optional fourth argument n can be used to limit the number of substitutions made:"

local Methods = {
	{ "%s+", " " },
	{ "are", "r" },
	{ "be", "b" },
	{ "you", "u" },
	{ "i%sam", "i'm" },
	{ "first", "1st" },
	{ "second", "2nd" },
	{ "third", "3rd" },
	{ "fourth", "4th" },
	{ "fifth", "5th" },
	{ "sixth", "6th" },
	{ "seventh", "7th" },
	{ "eigth", "8th" },
	{ "ninth", "9th" },
	{ "tenth", "10th" },
	{ "one", "1" },
	{ "two", "2" },
	{ "three", "3" },
	{ "four", "4" },
	{ "five", "5" },
	{ "six", "6" },
	{ "seven", "7" },
	{ "eight", "8" },
	{ "nine", "9" },
	{ "ten", "10" },
	{ "next", "nxt" },
	{ "i'm", "im" },
	{ ", but", ";" },
	{ ", and", ";" },
	{ ", or", ";" },
	{ "(%p)%s*", "%1" },
	{ "%sa%s", " "},
	{ "%san%s", " "},
	{ "%sthe%s", " "}
}


local function Compress(Message)
	Message = Message:lower()
	local OriginalLength = #Message
	local MaxAttempt = #Methods
	local Attempt = 0
	while (#Message > 140 and Attempt < MaxAttempt) do
		Attempt = Attempt + 1
		Message = Message:gsub(Methods[Attempt][1], Methods[Attempt][2])
		wait()
	end
	local NewLength = #Message
	print('Shortened by', OriginalLength - NewLength, 'characters.')
	print('Now', NewLength)
	print(Message)
end
Compress(Message)