Address name conflicts in EIEIO documentation (bug#31660)
* doc/misc/eieio.texi (Quick Start): Rename the class used in the example from 'record' to 'person'. (Building Classes): Advise user to check for name conflicts before naming a class. Add a missing apostrophe. (Making New Objects): Correct grammar. Rename the class used in the example from 'record' to 'my-class'.
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@ -88,11 +88,11 @@ framework for writing object-oriented applications in Emacs.
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use @eieio{} to create classes, methods for those classes, and
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instances of classes.
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Here is a simple example of a class named @code{record}, containing
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Here is a simple example of a class named @code{person}, containing
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three slots named @code{name}, @code{birthday}, and @code{phone}:
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@example
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(defclass record () ; No superclasses
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(defclass person () ; No superclasses
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((name :initarg :name
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:initform ""
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:type string
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@ -106,23 +106,23 @@ three slots named @code{name}, @code{birthday}, and @code{phone}:
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(phone :initarg :phone
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:initform ""
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:documentation "Phone number."))
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"A single record for tracking people I know.")
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"A class for tracking people I know.")
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@end example
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Each class can have methods, which are defined like this:
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@example
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(cl-defmethod call-record ((rec record) &optional scriptname)
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"Dial the phone for the record REC.
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(cl-defmethod call-person ((pers person) &optional scriptname)
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"Dial the phone for the person PERS.
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Execute the program SCRIPTNAME to dial the phone."
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(message "Dialing the phone for %s" (oref rec name))
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(message "Dialing the phone for %s" (oref pers name))
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(shell-command (concat (or scriptname "dialphone.sh")
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" "
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(oref rec phone))))
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(oref pers phone))))
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@end example
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@noindent
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In this example, the first argument to @code{call-record} is a list,
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In this example, the first argument to @code{call-person} is a list,
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of the form (@var{varname} @var{classname}). @var{varname} is the
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name of the variable used for the first argument; @var{classname} is
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the name of the class that is expected as the first argument for this
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@ -130,17 +130,17 @@ method.
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@eieio{} dispatches methods based on the type of the first argument.
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You can have multiple methods with the same name for different classes
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of object. When the @code{call-record} method is called, the first
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of object. When the @code{call-person} method is called, the first
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argument is examined to determine the class of that argument, and the
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method matching the input type is then executed.
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Once the behavior of a class is defined, you can create a new
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object of type @code{record}. Objects are created by calling the
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object of type @code{person}. Objects are created by calling the
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constructor. The constructor is a function with the same name as your
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class which returns a new instance of that class. Here is an example:
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@example
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(setq rec (record :name "Eric" :birthday "June" :phone "555-5555"))
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(setq pers (person :name "Eric" :birthday "June" :phone "555-5555"))
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@end example
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@noindent
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@ -157,19 +157,19 @@ first argument should be an object of a class which has had this
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method defined for it. In this example it would look like this:
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@example
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(call-record rec)
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(call-person pers)
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@end example
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@noindent
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or
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@example
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(call-record rec "my-call-script")
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(call-person pers "my-call-script")
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@end example
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In these examples, @eieio{} automatically examines the class of
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@code{rec}, and ensures that the method defined above is called. If
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@code{rec} is some other class lacking a @code{call-record} method, or
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@code{pers}, and ensures that the method defined above is called. If
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@code{pers} is some other class lacking a @code{call-person} method, or
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some other data type, Emacs signals a @code{cl-no-applicable-method}
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error. @ref{Signals}.
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@ -270,10 +270,18 @@ by a symbol with the name @var{class-name}. @eieio{} stores the structure of
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the class as a symbol property of @var{class-name} (@pxref{Symbol
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Components,,,elisp,GNU Emacs Lisp Reference Manual}).
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When defining a class, @eieio{} overwrites any preexisting variable or
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function bindings for the symbol @var{class-name}, which may lead to
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undesired consequences. Before naming a new class, you should check
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for name conflicts. To help avoid cross-package conflicts you should
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choose a name with the same prefix you chose for the rest of your
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package's functions and variables (@pxref{Coding
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Conventions,,,elisp,GNU Emacs Lisp Reference Manual}).
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The @var{class-name} symbol's variable documentation string is a
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modified version of the doc string found in @var{options-and-doc}.
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Each time a method is defined, the symbol's documentation string is
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updated to include the methods documentation as well.
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updated to include the method's documentation as well.
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The parent classes for @var{class-name} is @var{superclass-list}.
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Each element of @var{superclass-list} must be a class. These classes
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@ -625,10 +633,10 @@ function of @code{:initform}.
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@node Making New Objects
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@chapter Making New Objects
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Suppose we have a simple class is defined, such as:
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Suppose we have defined a simple class, such as:
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@example
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(defclass record ()
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(defclass my-class ()
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( ) "Doc String")
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@end example
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@ -636,10 +644,10 @@ Suppose we have a simple class is defined, such as:
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It is now possible to create objects of that class type.
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Calling @code{defclass} has defined two new functions. One is the
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constructor @var{record}, and the other is the predicate,
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@var{record}-p.
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constructor @var{my-class}, and the other is the predicate,
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@var{my-class}-p.
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@defun record object-name &rest slots
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@defun my-class object-name &rest slots
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This creates and returns a new object. This object is not assigned to
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anything, and will be garbage collected if not saved. This object
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@ -657,7 +665,7 @@ can do any valid Lispy thing you want with it, such as
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Example of creating an object from a class:
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@example
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(record :value 3 :reference nil)
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(my-class :value 3 :reference nil)
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@end example
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@end defun
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