OpenEuphoria

Re: Error Trapping

• Posted by "Boehme, Gabriel" <gboehme at MUSICLAND.COM> Feb 26, 1999
• 455 views

Ferlin <ferlin at SANDW.NET> wrote:

>        Is there a way to trap errors in Euphoria?  I am working
>on a project that involves an index of procedures and functions, the
>problem I am having is when someone enters the name of a function, if
>they do not have the proper number of parameters for that particular
>function Euphoria Issues an Error and aborts the program.  Is there a
>way I could trap this parameters error and issue and error message?

This is a good question. Currently, when you get a routine_id(), you have to
know in advance how many parameters it requires, what their types are, and
whether the routine is a procedure or a function. I think it would be kinda
neat if there were another function added to the routine_id() family:

s = routine_info(id)

Where s would be a sequence containing the relevant data:

R_TYPE = 1,     -- integer value indicating if this is a
                -- procedure or a function
    R_PROCEDURE = 1,
    R_FUNCTION = 2,

R_PARM_DATA = 2 -- sequence containing the routine id's of all the
                -- parameter types for this routine
                -- number of parms = length(s[R_PARM_DATA])

Obviously, this kind of thing would at least require the built-in types
(atom(), sequence(), etc.) to return valid routine_id() values, so that the
R_PARM_DATA sequence always gives us valid routine id's.

With this kind of thing available, it would be possible to completely verify
all aspects of a user-entered routine -- how many parameters, what kind of
parameters, and if we should expect a return value.


Gabriel Boehme