H

-handleQueryWithUnboundKey: method, Handling Key Lookup Failures

handlers and Cocoa exceptions, Exceptions in Cocoa–A Cocoa exception handling example

-handleTakeValue:forUnboundKey: method, Handling Key Lookup Failures

-hash method, Identifying objects and classes, Identifying objects and classes

header files, Declaring a category, Runtime Environment

declaring categories in, Declaring a category

runtime interfaces in, Runtime Environment