local function __TS__ArrayFlatMap(self, callback, thisArg)
    local result = {}
    local len = 0
    for i = 1, #self do
        local value = callback(thisArg, self[i], i - 1, self)
        if __TS__ArrayIsArray(value) then
            for j = 1, #value do
                len = len + 1
                result[len] = value[j]
            end
        else
            len = len + 1
            result[len] = value
        end
    end
    return result
end