From: Jano Svitok <jan.svitok@...>
Date: 2007-09-20T03:17:15+09:00
Subject: Re: exceptions and eval'ing a string

On 9/19/07, Chris Hall <christopher.k.hall@gmail.com> wrote:
> Here's my situation
> and this works...however, the difference is that if an exception is
> thrown as part of the Task's action (when it is run) eval craps out with
> an exception like
>
> (eval):15
>
> and it brings down the entire script, which is a bad thing because i'm
> running each task in a thread.  this doesn't happen obviously when i'm
> not eval'ing.

You can handle those exceptions by adding 'rescue' clause to your run method.
i.e.
def run
     begin
         @action.call...
    rescue Exception => ex
         # do whatever you want with ex
    end
end

You have to
Note: in this case the begin and end may be omitted:

def run
     @action.call...
rescue Exception => ex
     # do whatever you want with ex
end

To catch syntax errors, you have to add begin/rescue/end around the
eval command.

Have a look at ruby exception hierarchy in zenspider's Ruby QuickRef,
and carefully consider what do you want to catch and what not (to
allow ctrl-break to function etc.)

Finally, you can control exception propagation using Thread.abort_on_exception.

HTH,

Jano