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From: "Rego, P." <pvrego@gmail.com>
Newsgroups: comp.lang.ada
Subject: Pop function
Date: Wed, 14 Dec 2011 16:06:26 -0800 (PST)
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Date: 2011-12-14T16:06:26-08:00
List-Id: <comp.lang.ada>

Hello, 

Given a list type 
   type T_List is
      record
         Next : access T_List;
         Item : Integer;
      end record;
   T_List_Ptr is access T_List;

Is it right to implement a pop function like the following? (Free is an Unchecked_Deallocation)
   function Pop (Sender : access T_List) return Integer is
      Current_Sender_Ptr : T_List_Ptr := T_List_Ptr (Sender);
      Current_Item : constant T_List := Sender.Item;
   begin
      if Sender /= null then
         if Sender.Next /= null then
            Current_Sender_Ptr := T_List_Ptr (Current_Sender_Ptr.Next);
         end if;
		 Free (Current_Sender_Ptr);
         return Current_Item;
      else 
         return 0;
      end if;
   end Pop;

I mean, if I set Current_Sender_Ptr := T_List_Ptr (Current_Sender_Ptr.Next), it's equivalent to Sender := Sender.Next? (which I could not do directly due to in this case it would not be allowed an anonymous reference, right?)