Hi, I have some questions on error reporting.
I wrote this verb, I thought could be handy alongside the assert verb in
the standard library:
assertno =: 0 0$([ 13!:8~ ],~(LF,'| '),~ (9!:8'') {::~ <:@[)&>/@[^:(0 e. ])
it takes as x: error_number;'message', and as y the same as for assert (i.
e. it throws the error if 0 is an element in y). The error thrown will be
error number as specified, have a default header (as per 9!:8'') and an
additional custom text. For instance:
(3;'my message') assertno 0
|domain error
| my message: assertno
| (3;'my message') assertno 0
It allows passing a bit more context to a user, in my opinion useful, to
give more info instead of a mere assertion error, especially in library
code/OOP contexts.
That said, is such use of the error numbers/messages
recommended/allowed/frowned upon/silly?
Another question I have with regards to errors happening with a changed
locale.
I have:
ret=: coname''
cocurrent 'other'
do_stuff'' NB. could throw error
cocurrent ret
If do_stuff errors, the code ends up in the 'other' locale, which is
especially bad if it happens in library code taking for instance a user
verb it doesn't have control over.
Now I'd like to wrap the "do stuff" in a try-catch, such that in the catch,
the locale is reset to ret if do_stuff throws an error, to afterwards
re-throw the exact same error. I tried to find a solution, but using (dberm
dbsig dberr)'' sort of jumbles the message. Is there a better way of simply
forwarding the error without touching it?
Thanks,
Jan-Pieter
PS: I'm preparing an update to my types_dict addon, that's why I'm coming
up with so many questions.
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