variables - 在 Lua 中控制变量范围；它正在改变两个 Vars

Question

我不明白为什么 lua 会改变这两个变量，尽管我的理解是函数之外的那个不应该被触及。

这是怎么回事，我该如何保持“攻击者”变量不变？

谢谢!

local attacker = { 0,-1 }

local function test()

    local hitPattern = attacker

    print( "----------->> attacker", # attacker )

    --Set Loop Method
    if hitPattern[ # hitPattern ] == -1 then
        hitPattern[ # hitPattern ] = nil
    end

    print( "----->> attacker", # attacker )

end
test()
----------->> attacker 2
----->> attacker 1

Answer 1

来自 Lua 5.2 reference manual :

Tables, functions, threads, and (full) userdata values are objects: variables do not actually contain these values, only references to them. Assignment, parameter passing, and function returns always manipulate references to such values; these operations do not imply any kind of copy.

因此，当您分配时:

local hitPattern = attacker

变量hitPattern和attacker都引用同一个表，当你修改一个时，另一个也会改变。