Lua 5.4: question about label visibility rule

[Arnaud Delobelle <arnodel@...>]

Hi all,

In the Lua 5.4 docs it says the following.

    A label should not be declared where a label with the same
    name is visible, even if this other label has been declared
    in an enclosing block.

I have found the following test in the Lua 5.4.3 Test Suite (available
here: http://www.lua.org/tests/), in the file goto.lua (starting line
223):

local function testG (a)
  if a == 1 then
    goto l1
    error("should never be here!")
  elseif a == 2 then goto l2
  elseif a == 3 then goto l3
  elseif a == 4 then
    goto l1 -- go to inside the block
    error("should never be here!")
    ::l1:: a = a + 1 -- FIRST DECLARATION OF l1
  else
    goto l4
    ::l4a:: a = a * 2; goto l4b
    error("should never be here!")
    ::l4:: goto l4a
    error("should never be here!")
    ::l4b::
  end
  do return a end
  ::l2:: do return "2" end
  ::l3:: do return "3" end
  ::l1:: return "1" -- SECOND DECLARATION OF l1
end

In this function the label ::l1:: is declared twice, once in the
"elseif a == 4" clause and once at the end of the function.  In my
understanding, the second declaration of this label is visible at the
point where the first declaration is made.  That would contravene the
rule I have quoted above.

This must mean that I am misunderstanding the meaning of the quoted
rule.  Could anyone please help me understand it?

Regards,

-- 
Arnaud