# Association List For Storing Name-Value Pairs

    /*
    **	(c) COPYRIGHT MIT 1995.
    **	Please first read the full copyright statement in the file COPYRIGH.
    */

This Assoctiation List class is closely related to the HTList Class as it simply is a list of a specific list element containing a characters based name/value pair. Lookups from association list are not case-sensitive.

This module is implemented by HTAssoc.c, and it is a part of the W3C Sample Code Library.

    #ifndef HTASSOC_H
    #define HTASSOC_H

    #include "HTList.h"

    typedef HTList HTAssocList;

    typedef struct {
        char * name;
        char * value;
    } HTAssoc;

### Creation and Deletetion Methods

These methods create and deletes and association list

    extern HTAssocList * HTAssocList_new (void);
    extern BOOL 	     HTAssocList_delete (HTAssocList * alist);

### Add an Element to a List

We have two methods for adding new elements - you can either add unconditionally or replace any existing element with the same name but a new value. A new list element is added to the beginning of the list so that it is the first element just after the head element.

    extern BOOL HTAssocList_addObject (HTAssocList * alist,
    				   const char * name, const char * value);

    extern BOOL HTAssocList_replaceObject (HTAssocList * list,
    				       const char * name, const char * value);

### Remove an Element from a List

Remove the element with the given name from the list.

    extern BOOL HTAssocList_removeObject (HTAssocList * list, const char * name);

### Search for Elements in a list

We have a small set of methods for searching a specific element within a list.

    extern char * HTAssocList_findObject (HTAssocList * alist, const char * name);

### Get Name and Values

Use this to get the name and value of a assoc object

    #define HTAssoc_name(me)	((me) ? (me)->name : NULL)
    #define HTAssoc_value(me)	((me) ? (me)->value : NULL)

### Traverse list

Fast macro to traverse the list. Call it first with copy of list header: it returns the first object and increments the passed list pointer. Call it with the same variable until it returns NULL.

    #define	HTAssocList_nextObject(me) \
    	((me) && ((me) = (me)->next) ? (me)->object : NULL)

    #endif /* not HTASSOC_H */