Re: List container strawman 1.2

[Ted Dennison<dennison@telepath.com>]

In article <87668ivpw8.fsf@deneb.enyo.de>, Florian Weimer says...
>You should not call it a "bounded error" because that would be
>confusing.  Such errors result in erroneous execution with typical
>implementations.  For debugging, we might add an additional variable

I thought the whole point of "bounded errors" was that they *don't* result in
erroneous executions. Instead, there's a certian defined set of nasty things
that may happen (vs. the infamous "nasal monkeys" you get when you say
"erronious").

>parameter to the generic, which can be used to enable debugging.  It
>should default to "no debugging", and in such cases, at least GNAT
>generates no code for "if Debugging then ... end if;" conditional
>statements.

That's a technique I have to say I've never used in final production code, and
is certianly not used anywhere in the rest of the current Ada library. Exactly
what benifit would we get from this? I don't think you can use it to switch
between safe active iterators and unsafe "Locations", as the declarations would
have to be different too.

>Regarding the the name of "Index", I would like to reserve this word
>for discrete types.  "Location" or "Position", as proposed by Jeffrey,
>is probably better.

Fair enough.

>What about terminating Iterator prematurely using an exception?  It's
>a bit ugly, granted, but with the "out" parameter approach, I've
>managed to forget to set the parameter more than once.  If the Quit
>parameter is going to stay, we shouldn't use a Boolean type for it,
>but a new enumeration type.

I suspect we would have some violent objections to that idea from some people
(Although its still an option for the user. Just handle it outside the Iterator
call). What would you say to the proposal we had to make it "in out" with a
default?


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T.E.D.    homepage   - http://www.telepath.com/dennison/Ted/TED.html

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