From: David Vallner <david@...>
Date: 2006-02-07T12:05:10+09:00
Subject: Re: reasons to use else inside rescue

Dňa Utorok 07 Február 2006 03:33 Mark Volkmann napísal:
> I understand that the code in the else part of a begin block is only
> executed if no exceptions are raised by code in the begin block.
> However, the same is true of code at the end of the begin block. Why
> not put the code there?
>
> For example, I believe these are equivalent.
>
> begin
>   do_something
> rescue
>   handle_exception
> else
>   do_more_stuff
> end
>
> begin
>   do_something
>   do_more_stuff
> rescue
>   handle_exception
> end
>
> I suppose a difference is that if "do_more_stuff" raises an exception,
> the first example can't rescue it and the second might. Is that the
> only difference?
>
> --
> R. Mark Volkmann
> Partner, Object Computing, Inc.

There's an else part in a begin / end block?! Oh dear. Heavens protect us...

It seems pretty equivalent to plain old:

 begin
    do_something
  rescue
    handle_exception
  end
  do_more_stuff

Do we have a syntax guru to elaborate on this?

That said, my wild guess would be that in the code fragment (apologies for 
using different method names):

  begin
    foo
  rescue
    bar
  else
    baz
  finally
    quux
  end

(*sic* - messiest code excerpt ever)

if #foo didn't raise an Exception, the order of executions would be #foo, 
#baz, and then #quux. That is, unless the else is nothing more than no-op 
syntactic sugar for just putting the statements after a begin / rescue / 
finally block.

David Vallner
Confused like hell