Re: try..catch for Lua 5.2?

[Duncan Cross <duncan.cross@...>]

On Mon, Sep 13, 2010 at 6:24 PM, Duncan Cross <duncan.cross@gmail.com> wrote:
> How about a syntax something like this:

Or, another variation - instead of a comma followed by a function
name, an optional assignment expression that can refer to the left
hand side:

  try
    -- ... [1]
  catch e = MyException(e) do
    -- ... [2]
  catch e = MyOtherException(e) do
    -- ... [3]
  catch e do
    -- ... [4]
  end

...which would be sugar for:

  try
    -- ... [1]
  catch _ERROR do
    do
      local e = MyException(_ERROR)
      if e then
        -- ... [2]
        _ERROR = nil
      end
    end
    if _ERROR then
      local e = MyOtherException(_ERROR)
      if e then
        -- ... [3]
        _ERROR = nil
      end
    end
    if _ERROR then
      local e = _ERROR
      -- ... [4]
    end
  end

(Except, of course, _ERROR wouldn't really exist as a named variable.)

-Duncan