Re: Generic_Rational

[Simon Wright <simon@pushface.org>]

hnptz@yahoo.de writes:

> Thanks, it's working now. Nevertheless a further question:
>
> Simon wrote
>
> "... When the test program says 
>
>    for Candidate in 2..2**15 loop 
>
> Candidate is of type Integer (see ARM 3.6(17..18)[1], so that when it 
> says ... "
>
> Does a loop from 2..2**15 exceed the bounds of an integer type by one
> ? (see also 3.5.4(21)). If so, then Candidate should be become a
> Long_Integer type following 3.6(19). What may be wrong with this
> interpretation?

(18) says "If the type of the range resolves to root_integer, then the
discrete_subtype_definition defines a subtype of the predefined type
Integer with bounds given by a conversion to Integer of the bounds of
the range"; and I'm pretty sure that means "the largest integer type
suported by the implementation".

GNAT's Integer is -2**31 .. 2**31 -1 , so 2**15 is well
within. Long_Integer is -2**63 .. 2**63 - 1.

   for Candidate in 2..2**31 loop
        >>> value not in range of type "Standard.Integer"
        >>> static expression fails Constraint_Check

   for Candidate in 2..2**63 loop
        >>> warning: non-static universal integer value out of range
        >>> warning: "Constraint_Error" will be raised at run time
        >>> value not in range of type "Standard.Integer"
        >>> static expression fails Constraint_Check