--- parser3/src/include/pa_stack.h	2003/01/28 09:48:16	1.17.2.2
+++ parser3/src/include/pa_stack.h	2006/04/09 13:38:47	1.25
@@ -1,14 +1,14 @@
 /** @file
 	Parser: stack class decl.
 
-	Copyright (c) 2001, 2003 ArtLebedev Group (http://www.artlebedev.com)
+	Copyright (c) 2001-2005 ArtLebedev Group (http://www.artlebedev.com)
 	Author: Alexandr Petrosian <paf@design.ru> (http://paf.design.ru)
 */
 
 #ifndef PA_STACK_H
 #define PA_STACK_H
 
-static const char* IDENT_STACK_H="$Date: 2003/01/28 09:48:16 $";
+static const char * const IDENT_STACK_H="$Date: 2006/04/09 13:38:47 $";
 
 #include "pa_config_includes.h"
 #include "pa_array.h"
@@ -20,25 +20,35 @@ public:
 	Stack(): ftop(0) {}
 
 	void push(T item) {
-		if(ftop<count()) // cell is already allocated?
-			put(ftop, item); // use it
+		if(ftop<this->count()) // cell is already allocated?
+			this->put(ftop, item); // use it
 		else
 			*this+=item; // append it
 		ftop++;
 	}
+
 	T pop() {
-		return get(--ftop);
+		return this->get(--ftop);
 	}
 
-	int top_index() { return ftop-1; }
-	void top_index(int top_index) { ftop=top_index+1; }
-	T 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