Lua字符串分割：gmatch分列的实战写法

-- 错误：含空段的串用否定模式，空段被吞
for seg in ("100,200,,400"):gmatch("[^,]+") do
    handle(seg)
end

local function splitKeep(s, sep)
    local out, pos = {}, 1
    while true do
        local i, j = s:find(sep, pos, true)
        if i == nil then
            out[#out + 1] = s:sub(pos)
            break
        end
        out[#out + 1] = s:sub(pos, i - 1)
        pos = j + 1
    end
    return out
end
local p = getplayerbyname("spl01")
local parts = splitKeep("100,200,,400", ",")
sendmsg(p, 1, #parts .. "/" .. parts[3])