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Copyright ©1994 by NeXT Computer, Inc. All Rights Reserved.
Foundation Kit Functions
Memory Allocation Functions
Get the Virtual Memory Page Size
unsigned NSPageSize(void)tab Returns the number of bytes in a page.
unsigned NSLogPageSize(void)tab Returns the binary log of the page size.
unsigned NSRoundDownToMultipleOfPageSize(unsigned byteCount)
tab Returns the multiple of the page size that is closest to, but not greater than, byteCount.
unsigned NSRoundUpToMultipleOfPageSize(unsigned byteCount)
tab Returns the multiple of the page size that is closest to, but not less than, byteCount.
Get the Amount of Real Memory
unsigned NSRealMemoryAvailable(void)tab Returns the number of bytes available in the RAM hardware.
Allocate or Free Virtual Memory
void *NSAllocateMemoryPages(unsigned byteCount)
tab Allocates the integral number of pages whose total size is closest to, but not less than, byteCount, with the pages guaranteed to be zero-filled.
void NSDeallocateMemoryPages(void *pointer, tab Deallocates memory that was allocated with
unsigned byteCount)tab tab NSAllocateMemoryPages().
void NSCopyMemoryPages(const void *source, tab Copies (or copies-on-write) byteCount bytes from source
void *destination, tab tab to destination.
unsigned byteCount)
Get a Zone
NSZone *NSCreateZone(unsigned startSize, tab Creates and returns a pointer to a new zone of startSize
unsigned granularity, tab tab bytes, which will grow and shrink by granularity bytes.
BOOL canFree)tab tab If canFree is NO, the allocator will never free memory, and malloc() will be fast.
NSZone *NSDefaultMallocZone(void)tab Returns the default zone, which is created automatically at startup. This is the zone used by the standard C function malloc().
NSZone *NSZoneFromPointer(void *pointer)tab Returns the zone for the pointer block of memory, or NULL if the block was not allocated from a zone. The pointer must be one that was returned by a prior call to an allocation function.
Allocate or Free Memory in a Zone
void *NSZoneMalloc(NSZone *zone, tab Allocates size bytes in zone, and returns a pointer to the
unsigned size)tab tab allocated memory.
void *NSZoneCalloc(NSZone *zone, tab Allocates enough memory from zone for numElems
unsigned numElems, tab tab elements, each with a size of numBytes bytes, and
unsigned numBytes)tab tab returns a pointer to the allocated memory. The memory is initialized with zeros.
void *NSZoneRealloc(NSZone *zone, tab Changes the size of the block of memory pointed to by
void *pointer, tab tab pointer to size bytes. It may allocate new memory to
unsigned size)tab tab replace the old, in which case it moves the contents of the old memory block to the new block, up to a maximum of size bytes. The pointer may be NULL.
void NSRecycleZone(NSZone *zone)tab Frees zone after adding any of its pointers still in use to the default zone. (This strategy prevents retained objects from being inadvertently destroyed.)
void NSZoneFree(NSZone *zone, tab Returns memory to the zone from which it was allocated.
void *pointer)tab The standard C function free() does the same, but spends time finding which zone the memory belongs to.
Name a Zone
void NSSetZoneName(NSZone *zone, tab Sets the specified zone's name to name, which can aid in
NSString *name)tab tab debugging.
NSString *NSZoneName(NSZone *zone)tab Returns the name of zone.
Object Allocation Functions
Allocate or Free an Object
NSObject *NSAllocateObject(Class aClass, tab Allocates and returns a pointer to an instance of aClass,
unsigned extraBytes, tab tab created in the specified zone (or in the default zone, if
NSZone *zone)tab tab zone is NULL). The extraBytes argument (usually zero) states the number of extra bytes required for indexed instance variables.
NSObject *NSCopyObject(NSObject *anObject, tab Creates and returns a new object that's an exact copy of
unsigned extraBytes, tab tab anObject. The second and third arguments have the
NSZone *zone)tab tab same meaning as in NSAllocateObject().
void NSDeallocateObject(NSObject *anObject)tab Deallocates anObject, which must have been allocated using NSAllocateObject().
Decide Whether to Retain an Object
BOOL NSShouldRetainWithZone(NSObject *anObject,
NSZone *requestedZone)tab Returns YES if requestedZone is NULL, the default zone, or the zone in which anObject was allocated. This function is typically called from inside an NSObject's copyWithZone: method, when deciding whether to retain anObject as opposed to making a copy of it.
Modify the Number of References to an Object
BOOL NSDecrementExtraRefCountWasZero(id anObject)
tab Returns YES if the externally maintained ªextra reference countº for anObject is zero; otherwise, this function decrements the count and returns NO.
void NSIncrementExtraRefCount(id anObject)tab Increments the externally maintained ªextra reference countº for anObject. The first reference (typically done in the +alloc method) isn't maintained externally, so there's no need to call this function for that first reference.
Error-Handling Functions
Change the Top-level Error Handler
NSUncaughtExceptionHandler *NSGetUncaughtExceptionHandler(void)
tab Returns a pointer to the function serving as the top-level error handler. This handler will process exceptions raised outside of any exception-handling domain.
void NSSetUncaughtExceptionHandler(NSUncaughtExceptionHandler *handler)
tab Sets the top-level error-handling function to handler. If handler is NULL or this function is never invoked, the default top-level handler is used.
Macros to Handle an Exception
NS_DURINGtab Marks the beginning of an exception-handling domain (a portion of code delimited by NS_DURING and NS_HANDLER). When an error is raised anywhere within the exception-handling domain, program execution jumps to the first line of code in the exception handler. It's illegal to exit the exception-handling domain by any other means than NS_VALUERETURN, NS_VOIDRETURN, or falling out the bottom.
NS_ENDHANDLERtab Marks the ending of an exception handler (a portion of code delimited by NS_HANDLER and NS_ENDHANDLER).
NS_HANDLERtab Marks the ending of an exception-handling domain and the beginning of the corresponding exception handler. Within the scope of the handler, a local variable called exception stores the raised exception. Code delimited by NS_HANDLER and NS_ENDHANDLER is never executed except when an error is raised in the preceding exception-handling domain.
value NS_VALUERETURN(value, type) tab Causes the method (or function) in which this macro occurs to immediately return value of type type. This macro can only be placed within an exception-handling domain.
NS_VOIDRETURNtab Causes the method (or function) in which this macro occurs to return immediately, with no return value. This macro can only be placed within an exception-handling domain.
Call the Assertion Handler from the Body of an Objective-C Method
NSAssert(BOOL condition, tab Calls the NSAssertionHandler object for the current thread
NSString *description) tab tab if condition is false. The description should explain the error, formatted as for the standard C function printf(); it need not include the object's class and method name, since they're passed automatically to the handler.
NSAssert1(BOOL condition, tab Like NSAssert(), but the format string description
NSString *description, tab tab includes a conversion specification (such as %s or %d)
arg)tab tab for the argument arg, in the style of printf(). You can pass an object in arg by specifying %@, which gets replaced by the string that the object's description method returns.
NSAssert2(BOOL condition, tab Like NSAssert1(), but with two arguments.
NSString *description,
arg1,
arg2)
NSAssert3(BOOL condition, tab Like NSAssert1(), but with three arguments.
NSString *description,
arg1,
arg2,
arg3)tab
NSAssert4(BOOL condition, tab Like NSAssert1(), but with four arguments.
NSString *description,
arg1,
arg2,
arg3,
arg4) tab
NSAssert5(BOOL condition, tab Like NSAssert1(), but with five arguments.
NSString *description,
arg1,
arg2,
arg3,
arg4,
arg5)
Call the Assertion Handler from the Body of a C Function
NSCAssert(BOOL condition, tab Calls the NSAssertionHandler object for the current thread
NSString *description) tab tab if condition is false. The description should explain the error, formatted as for the standard C function printf(); it need not include the function name, which is passed automatically to the handler.
NSCAssert1(BOOL condition, tab Like NSCAssert(), but the format string description
NSString *description, tab tab includes a conversion specification (such as %s or %d)
arg) tab tab for the argument arg, in the style of printf().
NSCAssert2(BOOL condition, tab Like NSCAssert1(), but with two arguments.
NSString *description,
arg1,
arg2)
NSCAssert3(BOOL condition, tab Like NSCAssert1(), but with three arguments.
NSString *description,
arg1,
arg2,
arg3)
NSCAssert4(BOOL condition, tab Like NSCAssert1(), but with four arguments.
NSString *description,
arg1,
arg2,
arg3,
arg4)
NSCAssert5(BOOL condition, tab Like NSCAssert1(), but with five arguments.
NSString *description,
arg1,
arg2,
arg3,
arg4,
arg5)
Validate a Parameter
NSParameterAssert(BOOL condition) tab Like NSAssert(), but the description passed to the assertion handler is ªInvalid parameter not satisfying: º followed by the text of condition (which can be any boolean expression).
NSCParameterAssert(BOOL condition) tab Like NSParameterAssert(), but to be called from the body of a C function.
Geometric Functions
Create Basic Structures
NSPoint NSMakePoint(float x, float y)tab Create an NSPoint having the coordinates x and y.
NSSize NSMakeSize(float w, float h)tab Create an NSSize having the specified width and height.
NSRect NSMakeRect(float x, float y, float w, float h) Create an NSRect having the specified origin and size.
NSRange NSMakeRange(unsigned int location, unsigned int length)
tab Create an NSRange having the specified location and length.
Get a Rectangle's Coordinates
float NSMaxX(NSRect aRect)tab Returns the largest x-coordinate value within aRect.
float NSMaxY(NSRect aRect)tab Returns the largest y-coordinate value within aRect.
float NSMidX(NSRect aRect)tab Returns the x-coordinate of the rectangle's center point.
float NSMidY(NSRect aRect)tab Returns the y-coordinate of the rectangle's center point.
float NSMinX(NSRect aRect)tab Returns the smallest x-coordinate value within aRect.
float NSMinY(NSRect aRect)tab Returns the smallest y-coordinate value withinaRect .
float NSWidth(NSRect aRect)tab Returns the width of aRect.
float NSHeight(NSRect aRect)tab Returns the height of aRect.
Modify a Copy of a Rectangle
NSRect NSInsetRect(NSRect aRect, tab Returns a copy of the rectangle aRect, altered by moving
float dX, tab tab the two sides that are parallel to the y-axis inwards by
float dY)tab tab dX, and the two sides parallel to the x-axis inwards by dY.
NSRect NSOffsetRect(NSRect aRect, tab Returns a copy of the rectangle aRect, with its location
float dX, tab tab shifted by dX along the x-axis and by dY along the
float dY)tab tab y-axis.
void NSDivideRect(NSRect inRect, tab Creates two rectangles, slice and remainder, from inRect,
NSRect *slice, tab tab by dividing inRect with a line that's parallel to one of
NSRect *remainder, tab tab inRect's sides (namely, the side specified by edgeÐ
float amount, tab tab either NSMinXEdge, NSMinYEdge, NSMaxXEdge, or
NSRectEdge edge)tab tab NSMaxYEdge). The size of slice is determined by amount, which measures the distance from edge.
NSRect NSIntegralRect(NSRect aRect)tab Returns a copy of the rectangle aRect, expanded outwards just enough to ensure that none of its four defining values (x, y, width, and height) have fractional parts. If aRect's width or height is zero or negative, this function returns a rectangle with origin at (0.0, 0.0) and with zero width and height.
Compute a Third Rectangle from Two Rectangles
NSRect NSUnionRect(NSRect aRect, tab Returns the smallest rectangle that completely encloses
NSRect bRect)tab tab both aRect and bRect. If one of the rectangles has zero (or negative) width or height, a copy of the other rectangle is returned; but if both have zero (or negative) width or height, the returned rectangle has its origin at (0.0, 0.0) and has zero width and height.
NSRect NSIntersectionRect(NSRect aRect, tab Returns the graphic intersection of aRect and bRect. If the
NSRect bRect)tab tab two rectangles don't overlap, the returned rectangle has its origin at (0.0, 0.0) and zero width and height. (This includes situations where the intersection is a point or a line segment.)
Test Geometric Relationships
BOOL NSEqualRects(NSRect aRect, tab Returns YES if the two rectangles aRect and bRect are
NSRect bRect)tab tab identical, and NO otherwise.
BOOL NSEqualSizes(NSSize aSize, tab Returns YES if the two sizes aSize and bSize are identical,
NSSize bSize)tab tab and NO otherwise.
BOOL NSEqualPoints(NSPoint aPoint, tab Returns YES if the two points aPoint and bPoint are
NSPoint bPoint)tab tab identical, and NO otherwise.
BOOL NSIsEmptyRect(NSRect aRect)tab Returns YES if the rectangle encloses no area at allÐthat is, if its width or height is zero or negative.
BOOL NSMouseInRect(NSPoint aPoint, tab Returns YES if the point represented by aPoint is located
NSRect aRect, tab tab within the rectangle represented by aRect. It assumes
BOOL flipped)tab tab an unscaled and unrotated coordinate system; the argument flipped should be YES if the coordinate system has been flipped so that the positive y-axis extends downward. This function is used to determine whether the hot spot of the cursor lies inside a given rectangle.
BOOL NSPointInRect(NSPoint aPoint, tab Performs the same test as NSMouseInRect(), but assumes
NSRect aRect)tab tab a flipped coordinate system.
BOOL NSContainsRect(NSRect aRect, tab Returns YES if aRect completely encloses bRect. For this
NSRect bRect)tab tab to be true, bRect can't be empty and none of its sides can touch any of aRect's.
Get a String Representation
NSString *NSStringFromPoint(NSPoint aPoint)tab Returns a string of the form ª{x=a; y=b}º, where a and b are the x- and y-coordinates of aPoint.
NSString *NSStringFromRect(NSRect aRect)tab Returns a string of the form ª{x=a; y=b; width=c; height=d}º, where a, b, c, and d are the x- and y-coordinates and the width and height, respectively, of aRect.
NSString *NSStringFromSize(NSSize aSize)tab Returns a string of the form ª{width=a; height=b}º, where a and b are the width and height of aSize.
Range Functions
Query a Range
BOOL NSEqualRanges(NSRange range1, tab Returns YES if range1 and range2 have the same
NSRange range2)tab tab locations and lengths.
unsigned NSMaxRange(NSRange range)tab Returns range.location + range.lengthÐin other words, the number one greater than the maximum value within the range.
BOOL NSLocationInRange(unsigned location, tab Returns YES if location is in range (that is, if location is
NSRange range)tab tab greater than or equal to range.location and location is less than NSMaxRange(range)).
Compute a Range from Two Other Ranges
NSRange NSUnionRange(NSRange range1, tab Returns a range whose maximum value is the greater of
NSRange range2)tab tab range1's and range2's maximum values, and whose location is the lesser of the two range's locations.
NSRange NSIntersectionRange(NSRange range1, tab Returns a range whose maximum value is the lesser of
NSRange range2)tab tab range1's and range2's maximum values, and whose location is the greater of the two range's locations. However, if the two ranges don't intersect, the returned range has a location and length of zero.
Get a String Representation
NSString *NSStringFromRange(NSRange range)tab Returns a string of the form: ª{location = a; length = b}º, where a and b are non-negative integers.
Hash Table Functions
Create a Table
NSHashTable *NSCreateHashTable(NSHashTableCallBacks callBacks,
unsigned capacity)tab Creates, and returns a pointer to, an NSHashTable in the default zone; the table's size is dependent on (but generally not equal to) capacity. If capacity is 0, a small hash table is created. The NSHashTableCallBacks structure callBacks has five pointers to functions (documented under ªTypes and Constantsº), with the following defaults: pointer hashing, if hash() is NULL; pointer equality, if isEqual() is NULL; no call-back upon adding an element, if retain() is NULL; no call-back upon removing an element, if release() is NULL; and a function returning a pointer's hexadecimal value as a string, if describe() is NULL. The hashing function must be defined such that if two data elements are equal, as defined by the comparison function, the values produced by hashing on these elements must also be equal. Also, data elements must remain invariant if the value of the hashing function depends on them; for example, if the hashing function operates directly on the characters of a string, that string can't change.
NSHashTable *NSCreateHashTableWithZone(NSHashTableCallBacks callBacks,
unsigned capacity, tab Like NSCreateHashTable(), but creates the hash table in
NSZone *zone)tab tab zone instead of in the default zone. (If zone is NULL, the default zone is used.)
NSHashTable *NSCopyHashTableWithZone(NSHashTable *table,
NSZone *zone)tab Returns a pointer to a new copy of table, created in zone and containing copies of table's pointers to data elements. If zone is NULL, the default zone is used.
Free a Table
void NSFreeHashTable(NSHashTable *table)tab Releases each element of the specified hash table and frees the table itself.
void NSResetHashTable(NSHashTable *table)tab Releases each element but doesn't deallocate the table. This is useful for preserving the table's capacity.
Compare Two Tables
BOOL NSCompareHashTables(NSHashTable *table1,
NSHashTable *table2)tab Returns YES if the two hash tables are equalÐthat is, if each element of table1 is in table2, and the two tables are the same size.
Get the Number of Items
unsigned NSCountHashTable(NSHashTable *table)
tab Returns the number of elements in table.
Retrieve Items
void *NSHashGet(NSHashTable *table, tab Returns the pointer in the table that matches pointer (as
const void *pointer)tab tab defined by the isEqual() call-back function). If there is no matching element, the function returns NULL
NSArray *NSAllHashTableObjects(NSHashTable *table)
tab Returns an array object containing all the elements of table. This function should be called only when the table elements are objects, not when they're any other data type.
NSHashEnumerator NSEnumerateHashTable(NSHashTable *table)
tab Returns an NSHashEnumerator structure that will cause successive elements of table to be returned each time this enumerator is passed to NSNextHashEnumeratorItem().
void *NSNextHashEnumeratorItem(NSHashEnumerator *enumerator)
tab Returns the next element in the table that enumerator is associated with, or NULL if enumerator has already iterated over all the elements.
Add or Remove an Item
void NSHashInsert(NSHashTable *table, tab Inserts pointer, which must not be NULL, into table. If
const void *pointer)tab tab pointer matches an item already in the table, the previous pointer is released using the release() call-back function that was specified when the table was created.
void NSHashInsertKnownAbsent(NSHashTable *table,
const void *pointer)tab Inserts pointer, which must not be NULL, into table. Unike NSHashInsert(), this function raises NSInvalidArgumentException if table already includes an element that matches pointer.
void *NSHashInsertIfAbsent(NSHashTable *table,tab If pointer matches an item already in table, this function
const void *pointer)tab tab returns the pre-existing pointer; otherwise, it adds pointer to the table and returns NULL.
void NSHashRemove(NSHashTable *table, tab If pointer matches an item already in table, this function
const void *pointer)tab tab releases the pre-existing item.
Get a String Representation
NSString *NSStringFromHashTable(NSHashTable *table)
tab Returns a string describing the hash table's contents. The function iterates over the table's elements, and for each one appends the string returned by the describe() call-back function. If NULL was specified for the call-back function, the hexadecimal value of each pointer is added to the string.
Map Table Functions
Create a Table
NSMapTable *NSCreateMapTable(NSMapTableKeyCallBacks keyCallBacks,
NSMapTableValueCallBacks valueCallBacks,
unsigned capacity)tab Creates, and returns a pointer to, an NSMapTable in the default zone; the table's size is dependent on (but generally not equal to) capacity. If capacity is 0, a small map table is created. The NSMapTableKeyCallBacks arguments are structures (documented under ªTypes and Constantsº) that are very similar to the call-back structure used by NSCreateHashTable(); in fact, they have the same defaults as documented for that function.
NSMapTable *NSCreateMapTableWithZone(NSMapTableKeyCallBacks keyCallBacks,
NSMapTableValueCallBacks valueCallBacks,
unsigned capacity, tab Like NSCreateMapTable(), but creates the map table in
NSZone *zone)tab tab zone instead of in the default zone. (If zone is NULL, the default zone is used.)
NSMapTable *NSCopyMapTableWithZone(NSMapTable *table,
NSZone *zone)tab Returns a pointer to a new copy of table, created in zone and containing copies of table's key and value pointers. If zone is NULL, the default zone is used.
Free a Table
void NSFreeMapTable(NSMapTable *table)tab Releases each key and value of the specified map table and frees the table itself.
void NSResetMapTable(NSMapTable *table)tab Releases each key and value but doesn't deallocate the table. This is useful for preserving the table's capacity.
Compare Two Tables:
BOOL NSCompareMapTables(NSMapTable *table1,
NSMapTable *table2)tab Returns YES if each key of table1 is in table2, and the two tables are the same size. Note that this function does not compare values, only keys.
Get the Number of Items
unsigned NSCountMapTable(NSMapTable *table)tab Returns the number of key/value pairs in table.
Retrieve Items
BOOL NSMapMember(NSMapTable *table, tab Returns YES if table contains a key equal to key. If so,
const void *key, tab tab originalKey is set to key, and value is set to the value that
void **originalKey, tab tab the table maps to key.
void **value)
void *NSMapGet(NSMapTable *table, tab Returns the value that table maps to key, or NULL if the
const void *key)tab tab table doesn't contain key.
NSMapEnumerator NSEnumerateMapTable(NSMapTable *table)
tab Returns an NSMapEnumerator structure that will cause successive key/value pairs of table to be visited each time this enumerator is passed to NSNextMapEnumeratorPair().
BOOL NSNextMapEnumeratorPair(NSMapEnumerator *enumerator,
void **key, tab Returns NO if enumerator has already iterated over all the
void **value)tab tab elements in the table that enumerator is associated with. Otherwise, this function sets key and value to match the next key/value pair in the table, and returns YES.
NSArray *NSAllMapTableKeys(NSMapTable *table)
tab Returns an array object containing all the keys in table. This function should be called only when the table keys are objects, not when they're any other type of pointer.
NSArray *NSAllMapTableValues(NSMapTable *table)
tab Returns an array object containing all the values in table. This function should be called only when the table values are objects, not when they're any other type of pointer.
Add or Remove an Item
void NSMapInsert(NSMapTable *table, tab Inserts key and value into table. If key matches a key
const void *key, tab tab already in the table, value is retained and the previous
const void *value)tab tab value is released, using the retain and release call-back functions that were specified when the table was created. Raises NSInvalidArgumentException if key is equal to the notAKeyMarker field of the table's NSMapTableKeyCallBacks structure.
void *NSMapInsertIfAbsent(NSMapTable *table, tab If key matches a key already in table, this function returns
const void *key, tab tab the pre-existing key; otherwise, it adds key and value to
const void *value)tab tab the table and returns NULL. Raises NSInvalidArgumentException if key is equal to the notAKeyMarker field of the table's NSMapTableKeyCallBacks structure.
void NSMapInsertKnownAbsent(NSMapTable *table,
const void *key, tab Inserts key (which must not be notAKeyMarker) and
const void *value)tab tab value into table. Unike NSMapInsert(), this function raises NSInvalidArgumentException if table already includes a key that matches key.
void NSMapRemove(NSMapTable *table, tab If key matches a key already in table, this function releases
const void *key)tab tab the pre-existing key and its corresponding value.
NSString *NSStringFromMapTable(NSMapTable *table)
tab Returns a string describing the map table's contents. The function iterates over the table's key/value pairs, and for each one appends the string ªa = b;\nº, where a and b are the key and value strings returned by the corresponding describe() call-back functions. If NULL was specified for the call-back function, a and b are the key and value pointers, expressed as hexadecimal numbers.
Miscellaneous Functions
Get Information about a User
NSString *NSUserName(void)
NSString *NSHomeDirectory(void)
NSString *NSHomeDirectoryForUser(NSString * userName)
Log an Error Message
void NSLog(NSString *format, ...)tab Writes to stderr an error message of the form:
ªtime processName processID formatº. The format argument to NSLog() is a format string in the style of the standard C function printf(), followed by an arbitrary number of arguments that match conversion specifications (such as %s or %d) in the format string. (You can pass an object in the list of arguments by specifying %@ in the format stringÐthis conversion specification gets replaced by the string that the object's description method returns.)
void NSLogv(NSString *format, va_list args)tab Like NSLog(), but the arguments to the format string are passed in a single va_list, in the manner of vprintf().
Get Localized Versions of Strings
NSString *NSLocalizedString(NSString *key,tab Returns a localized version of the string designated by key.
NSString *comment)tab tab The default string table (Localizable.strings) in the main bundle is searched for key. comment is ignored, but can provide information for translators.
NSString *NSLocalizedStringFromTable(NSString *key,
NSString *tableName, tab Like NSLocalizedString(), but searches the specified
NSString *comment)tab tab table.
NSString *NSLocalizedStringFromTableInBundle(NSString *key,
NSString *tableName, tab Like NSLocalizedStringFromTable, but uses the
NSBundle *aBundle, tab tab specified bundle instead of the application's main
NSString *comment)tab tab bundle.
Convert to and from a String
Class NSClassFromString(NSString *aClassName)tab
tab Returns the class object named by aClassName, or nil if none by this name is currently loaded.
SEL NSSelectorFromString(NSString *aSelectorName)
tab Returns the selector named by aSelectorName, or zero if none by this name exists.
NSString *NSStringFromClass(Class aClass)tab Returns an NSString containing the name of aClass.
NSString *NSStringFromSelector(SEL aSelector)tab Returns an NSString containing the name of aSelector.
Compose a Message To Be Sent Later to an Object
NSInvocation *NS_INVOCATION(Class aClass, tab Returns an NSInvocation object which you can later ask to
instanceMessage)tab tab dispatch instanceMessage to an instance of aClass. (You later use NSInvocation's setTarget: method to make a specific instance of aClass the receiver of the message, after which you use invoke to cause the message to be sent and getReturnValue: to retrieve the result.) Because this is a macro, message can be any Objective C message understood by an instance of aClass, even a message with multiple arguments.
NSInvocation *NS_MESSAGE(id anObject, tab Like NS_INVOCATION(), but the first argument is an
instanceMessage)tab tab instance of a class, rather than a class. The target of the message will be anObject, so later you don't use setTarget:, only invoke and getReturnValue:.
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.