Re: Ada and "early return" - opinion/practice question

["Randy Brukardt" <randy@rrsoftware.com>]

"Paul Rubin" <no.email@nospam.invalid> wrote in message 
news:87im5sutdt.fsf@nightsong.com...
> Shark8 <onewingedshark@gmail.com> writes:
>> Exceptions, typically.  Sometimes a return itself, typically in a
>> procedure though.
>
> This is interesting: I thought in the Java and C++ worlds, using
> exceptions to manage normal control flow was frowned on, ...

We're not talking about "normal control flow" here; we're talking about 
error conditions that typically represent a programming mistake. It's fine 
to use exceptions for that, because they should never occur. When they do, 
you don't really care how expensive they are (again, because they're rare).

If you have a normal case (such as not finding anything in a search), using 
exceptions would generally be considered wrong. Using them would break up 
cases that are logically related.

Ada does take a more flexible approach though. Most Ada programmers would 
rather handle the exception End_Error rather than fill their program with 
tests for end-of-file before every read. I/O is messy enough without putting 
the boundary conditions everywhere (or worse yet, *ignoring* the boundary 
conditions).

So no completely hard-and-fast rule for Ada.

                                          Randy.