Re: "unconstrained subtype in component declaration" vs "discriminant in constraint must appear alone"

[Mehdi Saada <00120260a@gmail.com>]

Please help figure out this:

 type CARDS is new cards_numbers range 1..52;
-->
        41:10 missing case values: -128 .. 0
        41:10 missing case values: 5 .. 127
        41:25 subtype of expression is not static, alternatives must cover base type
from --> 
[card in CARDS, of course]
 	case (card / 13) +1 is
            when 1 => put("Spades");
            when 2 =>put("Hearts");
            when 3 =>put("Spades");
            when 4 =>put("Clovers");
         end case;

how can the compiler not know that CARD is limited from 1 to 52, including 0 for the base type (type Cards_numbers is range 0..52)

also what's wrong here:
Context => 
      type Sets_of_Card is array (Nombre_cartes range <>) of Cards;
 type CARDS_SETS (Nb: Nombre_cartes := 0) is record
         Set: Sets_of_Card (1..Nb) := INITIALIZATION (Nb);
      end record;
pack.nb =  5
pack.set'last =  5
faulty line:
PACK := (pack.nb-1, Pack.Set(pack.set'First..Pack.Nb-1));
issue:
raised CONSTRAINT_ERROR : discriminant check failed

and why is this expression not rejected:
         Pack := (pack.nb+1, pack.set & Card);
while this one is rejected ? 
Pack := (pack.nb+1, pack.set & CARDS_SET'(1=> Card));
a95cop1.adb:126:39: invalid operand types for operator "&"
this works but overkill... -> Pack := (pack.nb+1, (pack.set with delta PACK.NB+1 => Card));