【进阶实战】Lua栈式配对：沙巴克公告模板的括号合法性校验

local function check(s)
    local l = #string.gsub(s, "%(", "")
    local r = #string.gsub(s, "%)", "")
    return l == r                 -- 只数个数，"( ) (" 也判合法
end

local CLOSE = {[")"] = "(", ["]"] = "[", ["}"] = "{"}
local function check(s)
    local st = {}
    for ch in string.gmatch(s, "%S") do
        if ch == "(" or ch == "[" or ch == "{" then
            st[#st + 1] = ch            -- 左括号压栈
        elseif CLOSE[ch] then
            if st[#st] ~= CLOSE[ch] then return false end
            st[#st] = nil               -- 配对成功弹栈
        end
    end
    return #st == 0
end
sendmsg(actor, 1, "沙巴克公告模板合法："
    .. tostring(check("({name} {count})")))