@copying
This manual documents EIEIO, an object framework for Emacs Lisp.
-Copyright @copyright{} 2007--2012 Free Software Foundation, Inc.
+Copyright @copyright{} 2007--2013 Free Software Foundation, Inc.
@quotation
Permission is granted to copy, distribute and/or modify this document
@comment node-name, next, previous, up
@top EIEIO
-@eieio{} (``Enhanced Implementation of Emacs Interpreted Objects'') is
-a CLOS (Common Lisp Object System) compatibility layer for Emacs Lisp.
-It provides a framework for writing object-oriented applications in
-Emacs.
+@eieio{} (``Enhanced Implementation of Emacs Interpreted Objects'')
+provides an Object Oriented layer for Emacs Lisp, following the basic
+concepts of the Common Lisp Object System (CLOS). It provides a
+framework for writing object-oriented applications in Emacs.
@ifnottex
@insertcopying
@item
Help system extensions for classes and methods.
@item
-Automatic texinfo documentation generator.
-@item
Several base classes for interesting tasks.
@item
Simple test suite.
Customization support in a class (extension to CLOS)
@end enumerate
-Here are some CLOS features that @eieio{} presently lacks:
+Here are some important CLOS features that @eieio{} presently lacks:
@table @asis
-@item Complete @code{defclass} tag support
-All CLOS tags are currently supported, but the following are not
-currently implemented correctly:
-@table @code
-@item :metaclass
-There is only one base superclass for all @eieio{} classes, which is
-the @code{eieio-default-superclass}.
-@item :default-initargs
+@item Method dispatch
+EIEO does not support method dispatch for built-in types and multiple
+arguments types. In other words, method dispatch only looks at the
+first argument, and this one must be an @eieio{} type.
+
+@item Support for metaclasses
+There is just one default metaclass, @code{eieio-default-superclass},
+and you cannot define your own. The @code{:metaclass} tag in
+@code{defclass} is ignored. Also, functions like `class-of' and
+`find-class', which should return instances of the metaclass, behave
+differently in @eieio{} in that they return symbols or plain structures
+instead.
+
+@item EQL specialization
+EIEIO does not support it.
+
+@item @code{:around} method tag
+This CLOS method tag is non-functional.
+
+@item :default-initargs in @code{defclass}
Each slot has an @code{:initarg} tag, so this is not really necessary.
-@end table
@item Mock object initializers
Each class contains a mock object used for fast initialization of
values can potentially cause modifications in the mock object. @eieio{}
should use a deep copy but currently does not.
-@item @code{:around} method tag
-This CLOS method tag is non-functional.
-
@end table
@node Building Classes
@comment node-name, next, previous, up
@chapter Building Classes
+First off, please note that this manual cannot serve as a complete
+introduction to object oriented programming and generic functions in
+LISP. Although EIEIO is not a complete CLOS implementation and also
+differs from CLOS in several aspects, it follows the same basic
+concepts. Therefore, it is highly recommended to learn these from a
+textbook or tutorial first, especially if you only know OOP from
+languages like C++ or Java. If on the other hand you are already
+familiar with CLOS, you should be aware that @eieio{} does not implement
+the full CLOS specification and also differs in some other aspects
+(@xref{Introduction}, and @ref{CLOS compatibility}).
+
A @dfn{class} is a definition for organizing data and methods
together. An @eieio{} class has structures similar to the classes
found in other object-oriented (OO) languages.
@item :type
An unquoted type specifier used to validate data set into this slot.
-@xref{(cl)Type Predicates}.
+@xref{Type Predicates,,,cl,Common Lisp Extensions}.
Here are some examples:
@table @code
@item symbol
Each class will be indexed using the texinfo labeled index
@var{indexstring} which is a two letter description.
-@xref{(texinfo) New Indices}.
+@xref{New Indices,,,texinfo,Texinfo manual}.
To use this command, the texinfo macro
with it, certain default methods or attributes can be added to all
objects. In CLOS, this would be named @code{STANDARD-CLASS}, and that
symbol is an alias to @code{eieio-default-superclass}.
-@refill
Currently, the default superclass is defined as follows:
@item :type
Specifier uses the @code{typep} function from the @file{cl}
-package. @xref{(cl)Type Predicates}. It therefore has the same issues as
-that package. Extensions include the ability to provide object names.
+package. @xref{Type Predicates,,,cl,Common Lisp Extensions}.
+It therefore has the same issues as that package. Extensions include
+the ability to provide object names.
@end table
Defclass also supports class options, but does not currently use values
@enumerate
@item
+Support for metaclasses and EQL specialization.
+@item
@code{:around} method key.
-
@item
Method dispatch for built-in types.
@item