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/** NSEnumerator abstrace class for GNUStep
Copyright (C) 1995, 1996 Free Software Foundation, Inc.
Written by: Andrew Kachites McCallum <mccallum@gnu.ai.mit.edu>
Date: March 1995
This file is part of the GNUstep Base Library.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110 USA.
<title>NSEnumerator class reference</title>
$Date$ $Revision$
*/
#import "common.h"
#import "Foundation/NSArray.h"
#import "Foundation/NSEnumerator.h"
#import "Foundation/NSException.h"
/**
* Simple class for iterating over a collection of objects, usually returned
* from an [NSArray] or similar.
*/
@implementation NSEnumerator
/**
* Returns all objects remaining in the enumeration as an array.<br />
* Calling this method 'exhausts' the enumerator, leaving it at the
* end of the collection being enumerated.
*/
- (NSArray*) allObjects
{
NSMutableArray *array;
id obj;
SEL nsel;
IMP nimp;
SEL asel;
IMP aimp;
array = [NSMutableArray arrayWithCapacity: 10];
nsel = @selector(nextObject);
nimp = [self methodForSelector: nsel];
asel = @selector(addObject:);
aimp = [array methodForSelector: asel];
while ((obj = (*nimp)(self, nsel)) != nil)
{
(*aimp)(array, asel, obj);
}
return array;
}
/**
* Returns next object in enumeration, or nil if none remain. Use code like
* <code>while (object = [enumerator nextObject]) { ... }</code>.
*/
- (id) nextObject
{
[self subclassResponsibility:_cmd];
return nil;
}
- (NSUInteger) countByEnumeratingWithState: (NSFastEnumerationState*)state
objects: (id*)stackbuf
count: (NSUInteger)len
{
IMP nextObject = [self methodForSelector: @selector(nextObject)];
int i;
state->itemsPtr = stackbuf;
state->mutationsPtr = (unsigned long*)self;
for (i = 0; i < len; i++)
{
id next = nextObject(self, @selector(nextObject));
if (nil == next)
{
return i;
}
*(stackbuf+i) = next;
}
return len;
}
@end
/**
* objc_enumerationMutation() is called whenever a collection mutates in the
* middle of fast enumeration.
*/
void objc_enumerationMutation(id obj)
{
[NSException raise: NSGenericException
format: @"Collection %@ was mutated while being enumerated", obj];
}
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