-- Implements equivalent functionality to JavaScript's `array.indexOf`,
-- implementing the interface and behaviors defined at:
-- https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf
--
-- This implementation is loosely based on the one described in the polyfill
-- source in the above link

return function<T>(array: Array<T>, searchElement: T, fromIndex: number?): number
	local fromIndex_ = fromIndex or 1
	local length = #array

	-- In the JS impl, a negative fromIndex means we should use length - index;
	-- with Lua, of course, this means that 0 is still valid, but refers to the
	-- end of the array the way that '-1' would in JS
	if fromIndex_ < 1 then
		fromIndex_ = math.max(length - math.abs(fromIndex_), 1)
	end

	for i = fromIndex_, length do
		if array[i] == searchElement then
			return i
		end
	end

	return -1
end
