put label after return?

[Rett Berg]

This doesn't appear to parse:

function showSkip()
  for i=1,10 do
    if i%2 == 0 then goto skip end
    return i
    ::skip::
  end
end

> label_after_return.lua:7: 'end' expected (to close 'for' at line 3) near '::'

In order for it to parse I need to use something like

  ...

  if true return i end

  ::skip::

Is there an alternative way to get this to parse without requiring a branch or similar?

Note: I don't mean fix the function, I am aware I could use an "else" instead or otherwise change the if block. I give the above example as demonstration only.

- Rett

[Rett Berg]

This is the actual code if anyone is interested. Basically I use the goto to get out of an inner loop that needs to be skipped.

--- use as an iterator.
Iter.__call = function(it)
  local li, k = it._li
  for key, v in it[1], it[2], it._nextK do
    k, it._nextK = key, key
    for i=-1,li,-1 do
      k, v = it[i](k, v); if k == nil then goto skip end
    end
    if true then return k, v end -- `if` is necessary for parser
    ::skip::
  end
end

[Sainan]

The keyword you are looking for is 'break'.

-- Sainan

[Martin Eden]

On 2025-11-30 16:30, Rett Berg wrote:
> This doesn't appear to parse:
>
> function showSkip()
> for i=1,10 do
> if i%2 == 0 then goto skip end
> return i
> ::skip::
> end
> end

"For syntactical reasons, labels in Lua are considered statements" [3.3.4]
"The return statement can only be written as the last statement of a
block." [3.3.4]

-- Martin

[Christophe Delord]

The branch can be avoided with a simple do…end block:

do return k, v end

::skip::

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[Rett Berg]

Perfect, I didn't even think of that!

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[Gé Weijers]

On Sun, Nov 30, 2025 at 6:32 AM Rett Berg <goog...@gmail.com> wrote:

[...] 

  ...

  if true return i end

  ::skip::

Is there an alternative way to get this to parse without requiring a branch or similar?

The usual idiom is

do

  return

end

::skip::

 

The compiler recognizes "if true" so your "if true then return end" produces the same code.

--

Gé