Re: Learning Ada (Was: unsigned type)

[Georg Bauhaus <rm.tsoh.plus-bug.bauhaus@maps.futureapps.de>]

anon wrote:
> the [RM] comments declare 
> the "Integer" basically as the "universal type is universal_integer" and the
> "Float" basically as the "universal type is universal_real".

Do they?  You mean, Humpty Dumpty is here again? ;-)


> Now, A integer may change it range when switching from a 16-bit system to a 
> 64-bit system, but the 16-bit code will work because the range of a 16-bit 
> integer is a subrange of a 64-bit integer.

Do you mean that every mention of Positive'Range, paradigmatically,
will not be a problem when going from a 16bit sized Positive range
to a 64bit sized Positive range?

Did you have a minute to consider the example given,

  S : String (Positive'First .. Positive'Last / 2);

on an 8GB RAM 64 bit system with 64bit sized Positive range?
It *won't* work.   Standard.Integer *did* create problems
when porting to other sizes, that's how I understand what
Randy Brukardt has said.

There exist algorithms that will work when the bit size
of Integer increases.  But that's not relevant.
Because Ada allows us to make this requirement
explicit by declaring, that an algorithm shall profit
from larger integer types:

  type Big_Num is range 0 .. System.Max_Int;

This does what sets Ada apart from most other languages:
the type distinguished application integer types and
ubiquitous library integer types.  A Good Thing when porting
a program.

[Other random remarks (really) and miscellanea portraying
knowledge of many Ada compilers skipped.]