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/**************************************************************************
* This program is Copyright (C) 1986-2002 by Jonathan Payne. JOVE is *
* provided by Jonathan and Jovehacks without charge and without *
* warranty. You may copy, modify, and/or distribute JOVE, provided that *
* this notice is included in all the source files and documentation. *
**************************************************************************/
#include "jove.h"
#include "list.h"
private List *
list_new()
{
List *new;
new = (List *) emalloc(sizeof (List));
new->car = NULL;
return new;
}
/* push an object to the beginning of list */
UnivPtr
list_push(list, element)
register List **list;
UnivPtr element;
{
List *new;
new = list_new();
new->cdr = *list;
new->car = element;
*list = new;
return element;
}
UnivPtr
list_pop(list)
List **list;
{
List *cell = *list;
UnivPtr element;
if (cell == NULL)
return NULL;
element = cell->car;
*list = cell->cdr;
free((UnivPtr) cell);
return element;
}
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