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Index: B T

⟦239440188⟧ TextFile

    Length: 1153 (0x481)
    Types: TextFile
    Names: »B«

Derivation

└─⟦f64eaa120⟧ Bits:30000752 8mm tape, Rational 1000, !projects 93 02 16
    └─⟦6f12a12be⟧ »DATA« 
        └─⟦this⟧

TextFile

package body Bounded_Queue_Generic is

    function Next_Index (Q : Queue; Index : Positive) return Positive is
    begin
        if Index = Q.Max_Elements then
            return 1;
        else
            return Index + 1;
        end if;
    end Next_Index;

    function Is_Empty (Q : Queue) return Boolean is
    begin
        return Q.Head = Q.Tail;
    end Is_Empty;

    procedure Make_Empty (Q : in out Queue) is
    begin
        Q.Head := Q.Tail;
    end Make_Empty;

    procedure Enqueue (Q : in out Queue; X : Element) is
    begin
        if Next_Index (Q, Q.Head) = Q.Tail then
            raise Constraint_Error;
        end if;
        Q.Values (Q.Head) := X;
        Q.Head := Next_Index (Q, Q.Head);
    end Enqueue;

    procedure Dequeue (Q : in out Queue) is
    begin
        if Is_Empty (Q) then
            raise Constraint_Error;
        end if;
        Q.Tail := Next_Index (Q, Q.Tail);
    end Dequeue;

    function First (Q : Queue) return Element is
    begin
        if Q.Head = Q.Tail then
            raise Constraint_Error;
        end if;
        return Q.Values (Q.Tail);
    end First;

end Bounded_Queue_Generic;