Lua中的范围规则

function functionScope()
    print( "\nIn function")
    print( "globalMainVariable: " .. globalMainVariable )
    if (localMainVariable ~= nil) then print( "localMainVariable: " .. localMainVariable ) end
end

globalMainVariable = "Visible"
local localMainVariable = "Visible"
functionScope()

但是下面的代码确实打印了localMainVariable.

globalMainVariable = "Visible"
local localMainVariable = "Visible"

function functionScope()
    print( "\nIn function")
    print( "globalMainVariable: " .. globalMainVariable )
    if (localMainVariable ~= nil) then print( "localMainVariable: " .. localMainVariable )  end
end

functionScope()

我知道它与声明localMainVariable的位置有关,但我认为将其设置为local会限制变量的范围.什么是实际规则？

谢谢

The scope of a local variable begins at the first statement after its
declaration and lasts until the last non-void statement of the
innermost block that includes the declaration.

Lua manual