/* 
 * Stack.h
 * Author: Hannah C. Tang (hctang@cs)
 *
 * Specification of public functions for the Stack struct
 * (the module parser)
 *
 * $Id: Stack.h,v 1.1 2001/12/18 00:24:16 cse466_t Exp $
 *
 */

#ifndef STACK_H
#define STACK_H

#include "common.h"

struct Stack;

/* Dynamically allocate and free Stack structs */
struct Stack* Stack_malloc( void );
void Stack_free( struct Stack *pS );

/* Push this (index, value, argument) tuple onto the stack.
 * Returns Bool_true if successful */
Bool Stack_push( struct Stack *pS, 
                 unsigned int index, enum Reader_TokenType t, unsigned int arg );

/* Pop an (index, value, argument) tuple off the stack.  
 * Returns Bool_true if successful */
Bool Stack_pop( struct Stack *pS,
                unsigned int *pIndex, enum Reader_TokenType *pT, unsigned int *pArg );

/* Return the number of elements in the stack */
unsigned int Stack_getNumElements( const struct Stack *pS );

/* Returns Bool_true if the stack has no elements */
Bool Stack_isEmpty( const struct Stack *pS );

#endif /* STACK_H */