【高级技巧】柯里化：预设参数的部分应用封装

local function curry(fn, arity)
    arity = arity or 2
    local function step(args)
        return function(a)
            args[#args + 1] = a
            if #args >= arity then
                return fn(table.unpack(args))
            end
            return step(args)
        end
    end
    return step({})
end
local function sendTo(chan, prefix, msg)
    sendmsg(nil, chan, prefix .. msg)
end
local sendSys = curry(sendTo, 3)(1)("【系统】")
local sendGuild = curry(sendTo, 3)(3)("【行会】")

local function demoCurry(actor)
    actor = getplayerbyname(actor)
    sendSys("祖玛教主将于 15 时刷新。")
    sendGuild("今晚 8 点沙巴克集结。")
    sendmsg(actor, 1, "两种通道已按预设发送。")
end