Re: Backtrace and enhanced catch

[Neil Jerram]

Kevin Ryde <address@hidden> writes:

> Neil Jerram <address@hidden> writes:
>>
>> The difference is that the enclosing call approach allows
>> code inbetween the lazy-catch and the error point to decide on a
>> different, more local strategy for handling the error, whereas the
>> hook approach doesn't.  I think it's clear that the enclosing call
>> approach is better,
>
> Yes.  Making a local decision is what I always seem to use lazy-catch
> for, in my case trapping selected system call errors but not
> interfering with the backtrace of others.

Not sure I understand.  Can you point me to an example?

>> the lazy-catch doc says that its handler must not return,
>
> It'd be nice if that could be relaxed, if it was easy to do.  In a
> couple of places I've wanted to return and continue past the
> lazy-catch form, having taken whatever action in the handler.  (An
> extra wrapping full `catch' makes that possible.)

Can you give an example to show what you mean?  I think it's
non-negotiable that if someone has coded a (throw ...) or an (error
...), execution cannot continue normally past that throw or error -
but perhaps that's not what you meant?

Regards,
        Neil