【入门夯实】Lua do end块：裁决之杖折价计算的临时变量生命周期

local function price(actor)
    local tmp = PRICE * 0.9
    sendmsg(actor, 1, "折价 " .. tmp)
    -- 200行业务……tmp全程可见，易误用
    return tmp
end

local function price(actor)
    local final
    do
        local tmp = PRICE * 0.9    -- 折价只在块内可见
        final = math.floor(tmp)
    end
    sendmsg(actor, 1, "裁决之杖成交 " .. final .. " 金")
    return final
end