Defining functions within `condition-case'

Defining functions within `condition-case'

[Jean Louis]

Is there any argument against following notion:

;; -*- lexical-binding: t; -*-

(condition-case my

    (defun my-2-hello ()
      (message "I am `my-hello'"))
      
  (error (message "%s" my)))

(my-2-hello) ➜ "I am ‘my-hello’"

I am testing it, it seems that it works.

The reason for this is website application development. I would like
to ensure that, in case of any errors, I can access a function to
inform me what went wrong. These errors should be presented over an
HTTP connection, and I do not intend to inspect them through Emacs
directly.

Jean Louis

Re: Defining functions within `condition-case'

[Michael Heerdegen via Users list for the GNU Emacs text editor]

Jean Louis <bugs@gnu.support> writes:

> ;; -*- lexical-binding: t; -*-
>
> (condition-case my
>
>     (defun my-2-hello ()
>       (message "I am `my-hello'"))
>       
>   (error (message "%s" my)))
>
> (my-2-hello) ➜ "I am ‘my-hello’"

You are aware that this doesn't catch runtime errors, only errors that
appear when evaluating the `defun'?  The above will not be of much use
unless your code contains lots of very strange and malformed defuns like
(defun 1).


Michael.

Re: Defining functions within `condition-case'

[Jean Louis]

* Michael Heerdegen via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org> [2024-12-25 22:57]:
> Jean Louis <bugs@gnu.support> writes:
> 
> > ;; -*- lexical-binding: t; -*-
> >
> > (condition-case my
> >
> >     (defun my-2-hello ()
> >       (message "I am `my-hello'"))
> >       
> >   (error (message "%s" my)))
> >
> > (my-2-hello) ➜ "I am ‘my-hello’"
> 
> You are aware that this doesn't catch runtime errors, only errors that
> appear when evaluating the `defun'?  The above will not be of much use
> unless your code contains lots of very strange and malformed defuns like
> (defun 1).

I am not aware how it works, did not do enough testing 🤔.

I will not use that approach, but must find way to report error on
HTTP or in HTTP manner, not within Emacs.

Is there way to replace debug reporting function?


-- 
Jean Louis

Re: Defining functions within `condition-case'

[Michael Heerdegen via Users list for the GNU Emacs text editor]

Jean Louis <bugs@gnu.support> writes:

> Is there way to replace debug reporting function?

You will be using batch mode for your use case?  Then first I'd look at

 (info "(elisp) Batch Mode")

if you not have yet.

Errors typically make your program stop unless they are handled.  If you
don't want to get error messages printed to the usual place, we get into
the realm of output streams I think.  For this see

  (info "(elisp) Read and Print")

and

  (info "(elisp) Output Streams")

in particular.


HTH,

Michael.