lace: Add a simple stack generic.

1-base/lace/source/lace-stack.adb

@@ -0,0 +1,45 @@
+package body lace.Stack
+is
+   use ada.Containers;
+
+
+   function to_Stack return Item
+   is
+      Self : Item;
+   begin
+      Self.reserve_Capacity (Count_type (initial_Capacity));
+      return Self;
+   end to_Stack;
+
+
+
+
+   procedure push (Self : in out Item;   E : in Element_T)
+   is
+      pragma assert (Check   => Self.Capacity >= Count_type (initial_Capacity),
+                     Message => "Stack has not been initialised.");
+   begin
+      Self.append (E);
+   end push;
+
+
+
+   function pop (Self : in out Item) return Element_T
+   is
+      Top : constant Element_t := Self.last_Element;
+   begin
+      Self.delete_Last;
+      return Top;
+   end pop;
+
+
+
+
+   function getCount (Self : in  Item) return Natural
+   is
+   begin
+      return Natural (Self.Length);
+   end getCount;
+
+
+end lace.Stack;

1-base/lace/source/lace-stack.ads

@@ -0,0 +1,29 @@
+private
+with
+     ada.Containers.Vectors;
+
+
+generic
+   type Element_t is private;
+   initial_Capacity : Positive;
+
+package lace.Stack
+is
+   type Item is private;
+
+   function  to_Stack return Item;
+
+
+   procedure push (Self : in out Item;   E : in Element_T);
+   function  pop  (Self : in out Item)   return Element_T;
+
+
+   function getCount (Self : in  Item)   return Natural;
+
+
+
+private
+   package Vectors is new ada.Containers.Vectors (Positive, Element_t);
+   type    Item   is new Vectors.Vector with null record;
+
+end lace.Stack;