The "Unknown:"s below indicate that an entry is incomplete.

• either the entry exist in the language, and please tell.
• either the entry doesn't exist in the language, and please tell so. The entry will be marked as such and won't appear as missing anymore.

See the various entries for C

• Category: Object Oriented, Statically typed

• Various

  isEqual

  equality / inequality (deep)

• Functions

  doesNotRecognizeSelector

  function called when a function is not defined (in dynamic languages)

• Control Flow

  NS_DURING a NS_HANDLER ... NS_ENDHANDLER	exception (catching)
  [NSException raise:name ...]	exception (throwing)

• Object Oriented & Reflexivity

  super	accessing parent method
  @interface c { ... } ... @end	class declaration
  self	current instance
  class	get the type/class corresponding to an object/instance/value
  respondsToSelector	has the method
  @interface child : parent { ... } ... @end	inheritance
  dealloc	manually call an object's destructor
  [ object method: para ]	method invocation
  [ object method ]	method invocation (with no parameter)
  [o copy]	object cloning
  [class_name alloc]	object creation
  isKindOfClass	testing class membership

• Strings

  characterAtIndex	accessing n-th character
  description	convert something to a string (see also string interpolation)
  [s substringWithRange:NSMakeRange(n, len)]	extract a substring
  rangeOfString	locate a substring
  [string rangeOfString:substring options:NSBackwardsSearch]	locate a substring (starting at the end)
  stringWithFormat	sprintf-like
  stringByAppendingString	string concatenation
  isEqualToString(1)	string equality & inequality
  isEqual	string equality & inequality
  length	string size
  @"..."	strings (with no interpolation of variables)
  NSString *	type name
  uppercaseString / lowercaseString / capitalizedString	uppercase / lowercase / capitalized string

• Bags and Lists

  [a insertObject:e atIndex:i]	adding an element at index (side-effect)
  arrayByAddingObject	adding an element at the end (return the new list (no side-effect))
  addObject	adding an element at the end (side-effect)
  indexOfObject, indexOfObjectIdenticalTo	find an element
  containsObject	is an element in the list
  componentsJoinedByString	join a list of strings in a string using a glue string
  lastObject	last element
  arrayByAddingObjectsFromArray	list concatenation
  [NSArray arrayWithObjects:a, b, c, nil]	list constructor
  count	list size
  objectAtIndex	list/array indexing
  sortedArrayUsingSelector, sortUsingSelector	sort

• Various Data Types

  objectForKey	dictionary (access: read)
  [h setObject:o forKey:k]	dictionary (access: write)
  [NSDictionary dictionaryWithObjectsAndKeys:b, a, d, c, nil]	dictionary (constructor)
  allKeys	dictionary (list of keys)
  removeObjectForKey	dictionary (remove by key)
  nil	optional value (null value)

  Unknown:

  optional value (null coalescing)

• Threads

  [NSThread detachNewThreadSelector:mainFunction toTarget:target withObject:obj]

  thread definition

Remarks

• (1) faster than isEqual