Foundation Data Types Reference

Overview

This document describes the data types and constants found in the Foundation framework.

Data Types

NSAppleEventManagerSuspensionID

Identifies an Apple event whose handling has been suspended. Can be used to resume handling of the Apple event.

typedef const struct __NSAppleEventManagerSuspension *NSAppleEventManagerSuspensionID;

NSComparator

Defines the signature for a block object used for comparison operations.

typedef NSComparisonResult (^NSComparator)(id obj1, id obj2);

NSArray *sortedArray = [array sortedArrayUsingComparator: ^(id obj1, id obj2) {

    if ([obj1 integerValue] > [obj2 integerValue]) {

        return (NSComparisonResult)NSOrderedDescending;

    }

    if ([obj1 integerValue] < [obj2 integerValue]) {

        return (NSComparisonResult)NSOrderedAscending;

    }

    return (NSComparisonResult)NSOrderedSame;

}];

NSDecimal

Used to describe a decimal number.

typedef struct {
      signed int _exponent:8;
      unsigned int _length:4;
      unsigned int _isNegative:1;
      unsigned int _isCompact:1;
      unsigned int _reserved:18;
      unsigned short _mantissa[NSDecimalMaxSize];
} NSDecimal;

NSHashEnumerator

Allows successive elements of a hash table to be returned each time this structure is passed to NSNextHashEnumeratorItem.

typedef struct {
      unsigned _pi;
      unsigned _si void *_bs;
} NSHashEnumerator;

NSHashTable

The opaque data type used by the functions described in “Hash Tables” in Foundation Functions Reference.

typedef struct _NSHashTable NSHashTable;

NSHashTableCallBacks

Defines a structure that contains the function pointers used to configure behavior of NSHashTable with respect to elements within a hash table.

typedef struct {
      unsigned (*hash)(NSHashTable *table, const void *);
      BOOL (*isEqual)(NSHashTable *table, const void *, const void  *);
      void (*retain)(NSHashTable *table, const void *);
      void (*release)(NSHashTable *table, void *);
      NSString *(*describe)(NSHashTable *table, const void *);
} NSHashTableCallBacks;

Fields

hash

Points to the function that must produce hash code for elements of the hash table. If NULL, the pointer value is used as the hash code. Second parameter is the element for which hash code should be produced.

isEqual

Points to the function that compares second and third parameters. If NULL, then == is used for comparison.

retain

Points to the function that increments a reference count for the given element. If NULL, then nothing is done for reference counting.

release

Points to the function that decrements a reference count for the given element, and if the reference count becomes 0, frees the given element. If NULL, then nothing is done for reference counting or releasing.

describe

Points to the function that produces an autoreleased NSString * describing the given element. If NULL, then the hash table produces a generic string description.

NSHashTableOptions

Specifies a bitfield used to configure the behavior of elements in an instance of NSHashTable.

typedef NSUInteger NSHashTableOptions

NSInteger

Used to describe an integer.

typedef long NSInteger;

NSMapEnumerator

Allows successive elements of a map table to be returned each time this structure is passed to NSNextMapEnumeratorPair.

typedef struct {
      unsigned _pi;
      unsigned _si;
      void *_bs;
} NSMapEnumerator;

NSMapTable

The opaque data type used by the functions described in “Managing Map Tables” in Foundation Functions Reference.

typedef struct _NSMapTable NSMapTable;

NSMapTableKeyCallBacks

The function pointers used to configure behavior of NSMapTable with respect to key elements within a map table.

typedef struct {
      unsigned (*hash)(NSMapTable *table, const void *);
      BOOL (*isEqual)(NSMapTable *table, const void *, const void  *);
      void (*retain)(NSMapTable *table, const void *);
      void (*release)(NSMapTable *table, void *);
      NSString *(*describe)(NSMapTable *table, const void *);
      const void *notAKeyMarker;
} NSMapTableKeyCallBacks;

Fields

hash

Points to the function which must produce hash code for key elements of the map table. If NULL, the pointer value is used as the hash code. Second parameter is the element for which hash code should be produced.

isEqual

Points to the function which compares second and third parameters. If NULL, then == is used for comparison.

retain

Points to the function which increments a reference count for the given element. If NULL, then nothing is done for reference counting.

release

Points to the function which decrements a reference count for the given element, and if the reference count becomes zero, frees the given element. If NULL, then nothing is done for reference counting or releasing.

describe

Points to the function which produces an autoreleased NSString * describing the given element. If NULL, then the map table produces a generic string description.

notAKeyMarker

No key put in map table can be this value. An exception is raised if attempt is made to use this value as a key

NSMapTableOptions

Specifies a bitfield used to configure the behavior of elements in an instance of NSMapTable.

typedef NSUInteger NSMapTableOptions

NSMapTableValueCallBacks

The function pointers used to configure behavior of NSMapTable with respect to value elements within a map table.

typedef struct {
      void (*retain)(NSMapTable *table, const void *);
      void (*release)(NSMapTable *table, void *);
      NSString *(*describe)(NSMapTable *table, const void *);
} NSMapTableValueCallBacks;

Fields

retain

Points to the function that increments a reference count for the given element. If NULL, then nothing is done for reference counting.

release

Points to the function that decrements a reference count for the given element, and if the reference count becomes zero, frees the given element. If NULL, then nothing is done for reference counting or releasing.

describe

Points to the function that produces an autoreleased NSString * describing the given element. If NULL, then the map table produces a generic string description.

NSPoint

Represents a point in a Cartesian coordinate system.

typedef struct _NSPoint {
      CGFloat x;
      CGFloat y;
} NSPoint;

Fields

x

The x coordinate.

y

The y coordinate.

NSPointArray

Type indicating a parameter is array of NSPoint structures.

typedef NSPoint *NSPointArray;

NSPointPointer

Type indicating a parameter is a pointer to an NSPoint structure.

typedef NSPoint *NSPointPointer;

NSRange

A structure used to describe a portion of a series—such as characters in a string or objects in an NSArray object.

typedef struct _NSRange {
      NSUInteger location;
      NSUInteger length;
} NSRange;

Fields

location

The start index (0 is the first, as in C arrays).

length

The number of items in the range (can be 0).

NSRangePointer

Type indicating a parameter is a pointer to an NSRange structure.

typedef NSRange *NSRangePointer;

NSRect

Represents a rectangle.

typedef struct _NSRect {
      NSPoint origin;
      NSSize size;
} NSRect;

Fields

origin

The origin of the rectangle (its starting x coordinate and y coordinate).

size

The width and height of the rectangle, as measured from the origin.

NSRectArray

Type indicating a parameter is array of NSRect structures.

typedef NSRect *NSRectArray;

NSRectPointer

Type indicating a parameter is a pointer to an NSRect structure.

typedef NSRect *NSRectPointer;

NSSize

Represents a two-dimensional size.

typedef struct _NSSize {
      CGFloat width;
      CGFloat height;
} NSSize;

Fields

width

The width.

height

The height.

NSSizeArray

Type indicating a parameter is an array of NSSize structures.

typedef NSSize *NSSizeArray;

NSSizePointer

Type indicating parameter is a pointer to an NSSize structure.

typedef NSSize *NSSizePointer;

NSSocketNativeHandle

Type for the platform-specific native socket handle.

typedef int NSSocketNativeHandle;

NSStringEncoding

Type representing string-encoding values.

typedef NSUInteger NSStringEncoding;

NSSwappedDouble

Opaque structure containing endian-independent double value.

typedef struct {
      unsigned long long v;
} NSSwappedDouble;

NSSwappedFloat

Opaque type containing an endian-independent float value.

typedef struct {
      unsigned int v;
} NSSwappedFloat;

NSTimeInterval

Used to specify a time interval, in seconds.

typedef double NSTimeInterval;

NSUncaughtExceptionHandler

Used for the function handling exceptions outside of an exception-handling domain.

typedef volatile void NSUncaughtExceptionHandler(NSException *exception);

NSUInteger

Used to describe an unsigned integer.

typedef unsigned long NSUInteger;

NSZone

Used to identify and manage memory zones.

typedef struct _NSZone NSZone;