chore：新的根节点

lua/lib/bit.lua

@@ -0,0 +1,68 @@
+local bit_ok, bit_ = pcall(require, "bit")       -- LuaJIT 内置 bit 库
+local bit32_ok, bit32_ = pcall(require, "bit32") -- Lua 5.2 内置 bit32 库
+
+---@alias fn_band fun(a: integer, b: integer): integer
+---@alias fn_bxor fun(a: integer, b: integer): integer
+---@type nil | { band: fn_band, bxor: fn_bxor }
+local bit53_ = nil -- Lua 5.3 引入的原生位运算操作符
+
+---@diagnostic disable-next-line: deprecated
+local load_func = load or loadstring
+if load_func then
+    ---将新语法放入字符串中，避免在旧版 Lua 中导致语法错误
+    local bit53_func, bit53_err = load_func("return {" ..
+        "band = function(a, b) return a & b end," ..
+        "bxor = function(a, b) return a ~ b end," ..
+        "}")
+    if bit53_func and not bit53_err then
+        bit53_ = bit53_func()
+    end
+end
+
+local bit = {}
+
+---@return integer
+function bit.bxor(a, b)
+    if bit_ok then
+        return bit_.bxor(a, b)
+    elseif bit32_ok then
+        return bit32_.bxor(a, b)
+    elseif bit53_ then
+        return bit53_.bxor(a, b)
+    end
+
+    local p, c = 1, 0
+    while a > 0 and b > 0 do
+        local ra, rb = a % 2, b % 2
+        if ra ~= rb then c = c + p end
+        a, b, p = (a - ra) / 2, (b - rb) / 2, p * 2
+    end
+    if a < b then a = b end
+    while a > 0 do
+        local ra = a % 2
+        if ra > 0 then c = c + p end
+        a, p = (a - ra) / 2, p * 2
+    end
+    return c
+end
+
+---@return integer
+function bit.band(a, b)
+    if bit_ok then
+        return bit_.band(a, b)
+    elseif bit32_ok then
+        return bit32_.band(a, b)
+    elseif bit53_ then
+        return bit53_.band(a, b)
+    end
+
+    local p, c = 1, 0
+    while a > 0 and b > 0 do
+        local ra, rb = a % 2, b % 2
+        if ra + rb > 1 then c = c + p end
+        a, b, p = (a - ra) / 2, (b - rb) / 2, p * 2
+    end
+    return c
+end
+
+return bit