Standarizing Octave:* warnings and errors ID

[Juan Pablo Carbajal]

Hi,

I would like to propose the creation of a "global" container of
Octave:* IDs for warning and errors. The ideal would be a dictionary,
but we do not have this data type so we can implement a function.

Now, to have them available in C++ code we need this function to be a
C++ function, right?

The interface I was thinking of is something like:

msgID (key)

where the only argument "key"
- can be an integer, in which case the string returned is extracted
from a list of strings ordered alphabetically.
- can be a string, in which case it is used as an identifier of the
ID. Example: "Octave:Invalid-fun-call" could be obtained with
msgID("invalid-call").

msgID (key, context)

the optional argument context adds the context to the ID. Examples
misgID ("invalid-call","quadgk") would produce "Octave:quadgk:Invalid-fun-call"
misgID ("invalid-call","quadgk:my_subfunction") would produce
"Octave:quadgk:my_subfunction:Invalid-fun-call"

The second call I am not sure about, since it de-standardizes the ID
and it really doesn't give more information since the warning and the
error will give the position where the error/warning was rised. (In
this regard the patch I send for quadgk.m may have to be changed).

What do you think?
What would be the best way of implementing something like this?

Thx