USING: help.markup help.syntax strings alien hashtables ; IN: cocoa.subclassing HELP: define-objc-class { $values { "hash" hashtable } { "imeth" "a sequence of instance method definitions" } } { $description "Defines a new Objective C class. The hashtable can contain the following keys:" { $list { { $link +name+ } " - a string naming the new class. Required." } { { $link +superclass+ } " - a string naming the superclass. Required." } { { $link +protocols+ } " - an array of strings naming protocols implemented by the superclass. Optional." } } "Every element of " { $snippet "imeth" } " defines an instance method, and is an array having the shape " { $snippet "{ name return args quot }" } ".:" { $table { "name" { "a selector name" } } { "name" { "a C type name; see " { $link "c-data" } } } { "args" { "a sequence of C type names; see " { $link "c-data" } } } { "quot" { "a quotation to be run as a callback when the method is invoked; see " { $link alien-callback } } } } "The quotation is run with the following values on the stack:" { $list { "the receiver of the message; an " { $link alien } " pointing to an instance of this class" } { "the selector naming the message; in most cases this value can be ignored" } "arguments passed to the message, if any" } "There is no way to define instance variables or class methods using this mechanism. However, instance variables can be simulated by using the receiver to key into a hashtable." } ; HELP: CLASS: { $syntax "CLASS: spec imeth... ;" } { $values { "spec" "an array of pairs" } { "name" "a new class name" } { "imeth" "instance method definitions" } } { $description "A sugared form of the following:" { $code "{ imeth... } \"spec\" define-objc-class" } "This word is preferred to calling " { $link define-objc-class } ", because it creates a class word in the " { $vocab-link "cocoa.classes" } " vocabulary at parse time, allowing code to refer to the class word in the same source file where the class is defined." } ; { define-objc-class POSTPONE: CLASS: } related-words ARTICLE: "objc-subclassing" "Subclassing Objective C classes" "Objective C classes can be subclassed, with new methods defined in Factor, using a parsing word:" { $subsection POSTPONE: CLASS: } "This word is actually syntax sugar for an ordinary word:" { $subsection define-objc-class } "Objective C class definitions are saved in the image. If the image is saved and Factor is restarted with the saved image, custom class definitions are made available to the Objective C runtime when they are first accessed from within Factor." ; IN: cocoa.subclassing ABOUT: "objc-subclassing"