Authors
- Richard Frith-Macdonald (
rfm@gnu.org)
-
Copyright: (C) 2010 Free Software Foundation, Inc.
- Declared in:
- GSLinkedList.h
GSLinkedList manages a list of GSListLink
objects.
Instance Variables
Method summary
- (void)
append: (
GSListLink*)link;
Appends link at the end of the linked
list managed by the receiver.
Retains the
link.
- (
NSUInteger)
count;
Returns the number of links in the list.
- (void)
empty;
Remove all links from the list and release them all.
- (
GSListLink*)
findEqual: (NSObject*)object
from: (
GSListLink*)start
back: (BOOL)aFlag;
Searches the linked list returning the link
containing object or nil
if it is not found.
The comparison is performed
using the
[NSObject -isEqual:]
method of object.
If
start is nil then the whole
list is searched.
This method will not
find links containing nil items.
- (
GSListLink*)
findIdentical: (NSObject*)object
from: (
GSListLink*)start
back: (BOOL)aFlag;
Searches the linked list returning the link
containing object or nil
if it is not found.
If start is
nil then the whole list is searched.
A direct pointer comparison is used to
determine equality.
- (
GSListLink*)
head;
Returns the first link in the list.
- (void)
insert: (
GSListLink*)link
after: (
GSListLink*)at;
Inserts other immediately after the receiver.
Retains the link.
- (void)
insert: (
GSListLink*)link
before: (
GSListLink*)at;
Inserts other immediately before the receiver.
Retains the link.
- (void)
removeLink: (
GSListLink*)link;
Removes the link from the receiver.
releases the link.
- (
GSListLink*)
tail;
Returns the last link in the list.
Instance Variables for GSLinkedList Class
@public NSUInteger count;
Description forthcoming.
@public GSListLink* head;
Description forthcoming.
@public GSListLink* tail;
Description forthcoming.
- Declared in:
- GSLinkedList.h
GSListLink provides simple doubly linked list
functionality to avoid the need to constantly
re-invent it (as the OpenStep/Cocoa APIs do not
provide this). The emphasis is on speed of operation
so instance variables are directly accessible and inline
functions are provided to manipulate them (without
error cehcking), but you can/should avoid these direct
access features unless speed is really critical.
A list may either be 'normal'... (where the
head/tail ends of the list have a nil
pointer to the previous/next link) or 'circular' in
which case the list is not terminated.
The
GSListLink item carries a minimal payload of a
single item which is retained by the link.
The
GSListLink owner is an optional pointer to an
object which 'owns' the link... a GSLinkedList
instance may use this to check link ownership when
manipulating links.
Instance Variables
Method summary
- (id)
initCircular;
Initialise the receiver as a link for a circular
linked list.
- (NSObject*)
item;
Return the item in the link.
- (
GSListLink*)
next;
Return the next item in the list containing the
receiver, or nil if there are no
more items.
- (
GSLinkedList*)
owner;
Return the list which owns the receiver or
nil if the receiver is not in a list.
- (
GSListLink*)
previous;
Return the previous item in the list containing the
receiver, or nil if there are no
more items.
- (void)
setItem: (NSObject*)anItem;
Set an item value by retaining it and releasing any
previous value.
Instance Variables for GSListLink Class
@public NSObject* item;
Description forthcoming.
@public GSListLink* next;
Description forthcoming.
@public GSLinkedList* owner;
Description forthcoming.
@public GSListLink* previous;
Description forthcoming.
typedef unsigned int NSUInteger;
Description forthcoming.
void GSLinkCircularInsertAfter(GSListLink* link, GSListLink* at);
Inserts link after at in a
circular list.
Arguments must not be
nil and link must not be in a
list (ie its next and previous pointers must point to
itsself).
void GSLinkCircularInsertBefore(GSListLink* link, GSListLink* at);
Inserts link before at in a
circular list.
Arguments must not be
nil and link must not be in a
list (ie its next and previous pointers must point to
itsself).
void GSLinkCircularRemove(GSListLink* link);
Removes link from any list it is in.
The link argument must not be
nil.
void GSLinkInsertAfter(GSListLink* link, GSListLink* at);
Inserts link after at in a
normal list.
Arguments must not be
nil and link must not be in a
list (ie its next and previous pointers must both be
nil).
void GSLinkInsertBefore(GSListLink* link, GSListLink* at);
Inserts link before at in a
normal list.
Arguments must not be
nil and link must not be in a
list (ie its next and previous pointers must both be
nil).
void GSLinkRemove(GSListLink* link);
Removes link from the list it is in.
The link argument must not be
nil.
GSListLink* GSLinkedListFindEqual(NSObject* object, GSLinkedList* list, GSListLink* from, BOOL back);
Searches from list to the end
looking for the first link containing
object (as determined by using object's
[NSObject -isEqual:]
method).
If from is
nil the list is search
from head or tail as appropriate to the
direction in which it is searched.
GSListLink* GSLinkedListFindIdentical(NSObject* object, GSLinkedList* list, GSListLink* from, BOOL back);
Searches from list to the end
looking for the first link containing
object (as determined by direct pointer
comparison).
If from is
nil the list is search
from head or tail as appropriate to the
direction in which it is searched.
void GSLinkedListInsertAfter(GSListLink* link, GSLinkedList* list, GSListLink* at);
Inserts link immediately after
at.
Updates the head, tail and count
variables of list.
Does not
retain link.
void GSLinkedListInsertBefore(GSListLink* link, GSLinkedList* list, GSListLink* at);
Inserts link immediately before
at.
Updates the head, tail and count
variables of list.
Does not
retain link.
void GSLinkedListMoveToHead(GSListLink* link, GSLinkedList* list);
Moves the link to the head of the
list if it is not already there.
void GSLinkedListMoveToTail(GSListLink* link, GSLinkedList* list);
Moves the link to the tail of the
list if it is not already there.
void GSLinkedListRemove(GSListLink* link, GSLinkedList* list);
Removes link from the list.
Updates the head, tail and count variables of
list.
Does not release
link.