Re: Shortcut logicals (was: Re: F200x )

[Martin Krischik <martin@krischik.com>]

Christoph Grein wrote:

>  > Robert A Duff wrote:
>  >
>  > > And the syntax rules forbid mixing "and" and "and then" -- you have
>  > > to use
>  > > parens.??All?of?these?("and",?"and?then",?"or",?"or?else",?"xor") are
>  > > lower precedence than most other operators in Ada.??So?you?can write:
>  >
>  > Are you sure? I did not find anything in the RM to support that. I
> checked
>  > both the RM and AARM:

> of course Robert is sure, if not, who else - you should know, he's
> deeply involved in Ada development.

Ok you are right,  I am a just bit weak on names.

> See RM 4.4(2..7).

For our friends from comp.lang.fortran: You can read it up at
http://www.adaic.com/standards/95lrm/html/RM-4-4.html:
 
> You'll find
> relation and relation gives an expression,
> relation and then relation also gives an expression.

> But there is no syntax rule to combine an expression with a relation.
> You can only combine a parenthesized expression (a primary) with a
> relation.

Sure, you are right. But that rule means that:

 X or Y and Z

is not valid either. Not that I ever noticed - I would always use '()' on
such a term.

>  > http://www.adaic.com/standards/95lrm/html/RM-4-5-1.html
>  > http://www.adaic.com/standards/95aarm/html/AA-4-5-1.html
>  >
>  > (To the Fortran comunity: the the first is the general public
> version, the
>  > later the compiler vendor version).
> 
> More precisely: The first is the binding reference manual, the second
> has further discussions, explanations and rationales without any binding
> character. Of course there should be no contradictions between the two.

You know me: I always try to use easy words.

Martin

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