Re: Dealing With Errors in Lua

[Enrico Colombini <erix@...>]

On 27/09/2013 17.50, Rena wrote:
> To determine the actual error now requires some string parsing which is a
> bit inefficient.

I've given some thought to this matter in the past (definitely not as 
much as you did) and one of the ideas for a compatible solution was to 
prepend error strings with an unique numeric code, e.g.:

  =a[i]
  [1234] stdin:1: attempt to index global 'a' (a nil value)

Far from ideal, and that's the reason why I didn't propose it, but at 
least the error code could be read with a simple pattern match.
(yes, I know, I can always patch the source)

Actually, what started me thinking about it was a need for error message 
localization, or 'translation' (not in a linguistic sense) for 
non-professional users of Lua-based DSLs.
If Lua used an error code, or (probably better, but non 
backward-compatible) an error object as index in a message table, it 
would be easier to switch language and/or customize error messages 
without messing with the source code.

Just old, sparse, incoherent thoughts.

--
  Enrico