--- parser3/src/include/pa_stack.h	2002/03/18 15:29:46	1.14
+++ parser3/src/include/pa_stack.h	2005/03/16 14:37:51	1.23
@@ -1,45 +1,54 @@
 /** @file
 	Parser: stack class decl.
 
-	Copyright (c) 2001, 2002 ArtLebedev Group (http://www.artlebedev.com)
+	Copyright (c) 2001-2004 ArtLebedev Group (http://www.artlebedev.com)
 	Author: Alexandr Petrosian <paf@design.ru> (http://paf.design.ru)
-
-	$Id: pa_stack.h,v 1.14 2002/03/18 15:29:46 paf Exp $
 */
 
 #ifndef PA_STACK_H
 #define PA_STACK_H
 
+static const char * const IDENT_STACK_H="$Date: 2005/03/16 14:37:51 $";
+
 #include "pa_config_includes.h"
 #include "pa_array.h"
 
 /// simple stack based on Array
-class Stack : public Array {
+template<typename T> class Stack: public Array<T> {
 public:
 
-	Stack(Pool& apool) : Array(apool), ftop(0) {
-	}
+	Stack(): ftop(0) {}
 
-	void push(Item *item) {
-		if(ftop<size()) // cell is already allocated?
+	void push(T item) {
+		if(ftop<this->count()) // cell is already allocated?
 			put(ftop, item); // use it
 		else
 			*this+=item; // append it
 		ftop++;
 	}
-	Item *pop() {
-		return get(--ftop);
+
+	T pop() {
+		return this->get(--ftop);
 	}
 
-	int top_index() { return ftop-1; }
-	void top_index(int top_index) { ftop=top_index+1; }
-	Item *top_value() { return get(top_index()); }
+	bool is_empty() { return ftop==0; }
+	size_t top_index() { return ftop; }
+	void set_top_index(size_t atop) { ftop=atop; }
+	T top_value() { 
+		assert(!is_empty());
+		return this->get(ftop-1); 
+	}
 
-private:
+	/// call this prior to collecting garbage [in unused part of stack there may be pointers(unused)]
+	void wipe_unused() {
+		if(size_t above_top_size=this->fused-ftop)
+			memset(&this->felements[ftop], 0, above_top_size*sizeof(T));
+	}
 
-	// deepest used index
-	int ftop;
+protected:
 
+	// deepest used index+1
+	size_t ftop;
 };
 
 #endif