Data commit

Task/Queue-Definition/Component-Pascal/queue-definition-1.pas

@@ -0,0 +1,81 @@
+MODULE Queue;
+IMPORT
+	Boxes;
+TYPE
+	Instance* = POINTER TO LIMITED RECORD
+		size: LONGINT;
+		first,last: LONGINT;
+		_queue: POINTER TO ARRAY OF Boxes.Box;
+	END;
+	
+	PROCEDURE (self: Instance) Initialize(capacity: LONGINT),NEW;
+	BEGIN
+		self.size := 0;
+		self.first := 0;
+		self.last := 0;
+		NEW(self._queue,capacity)
+	END Initialize;
+	
+	PROCEDURE New*(capacity: LONGINT): Instance;
+	VAR
+		aQueue: Instance;
+	BEGIN
+		NEW(aQueue);aQueue.Initialize(capacity);RETURN aQueue
+	END New;
+	
+	PROCEDURE (self: Instance) IsEmpty*(): BOOLEAN, NEW;
+	BEGIN
+		RETURN self.size = 0;
+	END IsEmpty;
+	
+	PROCEDURE (self: Instance) Capacity*(): LONGINT, NEW;
+	BEGIN
+		RETURN LEN(self._queue)
+	END Capacity;
+	
+	PROCEDURE (self: Instance) Size*(): LONGINT, NEW;
+	BEGIN
+		RETURN self.size
+	END Size;
+	
+	PROCEDURE (self: Instance) IsFull*(): BOOLEAN, NEW;
+	BEGIN
+		RETURN self.size = self.Capacity()
+	END IsFull;
+	
+	PROCEDURE (self: Instance) Push*(b: Boxes.Box), NEW;
+	VAR
+		i, j, newCapacity, oldSize: LONGINT;
+		queue: POINTER TO ARRAY OF Boxes.Box;
+	BEGIN
+		INC(self.size);
+		self._queue[self.last] := b;
+		self.last := (self.last + 1) MOD self.Capacity();
+		IF self.IsFull() THEN
+			(* grow queue *)
+			newCapacity := self.Capacity() + (self.Capacity() DIV 2);
+			(* new queue *)
+			NEW(queue,newCapacity);
+			(* move data from old to new queue *)
+			i := self.first; j := 0; oldSize := self.Capacity() - self.first + self.last;
+			WHILE (j < oldSize) & (j < newCapacity - 1) DO
+				queue[j] := self._queue[i];
+				i := (i + 1) MOD newCapacity;INC(j)
+			END;
+			self._queue := queue;self.first := 0;self.last := j
+		END
+	END Push;
+	
+	PROCEDURE (self: Instance) Pop*(): Boxes.Box, NEW;
+	VAR
+		b: Boxes.Box;
+	BEGIN
+		ASSERT(~self.IsEmpty());
+		DEC(self.size);
+		b := self._queue[self.first];
+		self._queue[self.first] := NIL;
+		self.first := (self.first + 1) MOD self.Capacity();
+		RETURN b
+	END Pop;
+	
+END Queue.

Task/Queue-Definition/Component-Pascal/queue-definition-2.pas

@@ -0,0 +1,17 @@
+DEFINITION Queue;
+
+	IMPORT Boxes;
+
+	TYPE
+		Instance = POINTER TO LIMITED RECORD
+			(self: Instance) Capacity (): LONGINT, NEW;
+			(self: Instance) IsEmpty (): BOOLEAN, NEW;
+			(self: Instance) IsFull (): BOOLEAN, NEW;
+			(self: Instance) Pop (): Boxes.Box, NEW;
+			(self: Instance) Push (b: Boxes.Box), NEW;
+			(self: Instance) Size (): LONGINT, NEW
+		END;
+
+	PROCEDURE New (capacity: LONGINT): Instance;
+
+END Queue.