【高级技巧】括号匹配栈：配置格式的栈校验封装

local PAIRS = { ["{"] = "}", ["["] = "]", ["("] = ")" }
local function checkBrackets(s)
    local stack = {}
    local where = {}
    for i = 1, #s do
        local ch = string.sub(s, i, i)
        if PAIRS[ch] then
            table.insert(stack, { ch = ch, pos = i })
        elseif ch == "}" or ch == "]" or ch == ")" then
            local top = table.remove(stack)
            if top == nil or PAIRS[top.ch] ~= ch then
                return false, "位置 " .. i .. " 括号不匹配"
            end
        end
    end
    if #stack > 0 then
        return false, "位置 " .. stack[#stack].pos .. " 括号未闭合"
    end
    return true
end