NAME¶

UList - circular, doubly-linked list class

SYNOPSIS¶

#include <Unidraw/ulist.h>

DESCRIPTION¶

UList implements a circular, doubly-linked list. The sentinel andeach entry in the list are instances of the UList class, eachcontaining a void pointer to the data they contain as well as pointersto the next and previous UList instance in the list. The sentinelUList instance is considered to represent the list.

PUBLICOPERATIONS¶

UList(void* = nil)

Create a new UList instance, optionally supplying the value for thevoid pointer it stores.

virtual ~UList()

Delete the entire list. Normally the sentinel, which represents thelist, is the entry that is deleted explicitly. Note that the data onthe list, stored as void*'s, cannot be deleted in this manner.

void Append(UList*)

void Prepend(UList*)

When performed on the sentinel, Append appends an element to the endof the list and Prepend prepends it to the beginning of the list.When performed on a UList instance other than the sentinel, Append hasthe effect of inserting its argument before the instance, while Prepend has the effect of inserting it after the instance.

void Remove(UList*)

Unlink the specified UList instance from the list it is in. Theobject on which this operation is called is irrelevant.

void Delete(void*)

Find the UList instance in this list containing the given voidpointer, remove it from the list it is in, and delete it.

UList* Find(void*)

Return the UList instance in this list containing the given voidpointer.

UList* First()

UList* Last()

UList* End()

UList* Next()

UList* Prev()

Return various UList instance in the list relative to this, i.e., as if it were the sentinel. End returns the sentinel (this) and is useful for detecting the end of an iteration through the list; the other operations are self-explanatory.

boolean IsEmpty()

Return whether or not the list has any elements.

void* operator()()

Return the void pointer that the UList stores.

UList* operator[](int i)

Return the ith UList in the list, where the next element is the first, etc.