@setchapternewpage odd
@synindex vr fn
-@c $Id: sos.texinfo,v 1.5 1993/03/10 22:16:27 cph Exp $
+@c $Id: sos.texinfo,v 1.6 1994/06/01 20:15:23 cph Exp $
@set TITLE The SOS Reference Manual
-@set EDITION 1.5
-@set UPDATED 10 March 1993
-@set UPDATE-MONTH March 1993
+@set EDITION 1.6
+@set UPDATED 1 June 1994
+@set UPDATE-MONTH June 1994
@ifinfo
-Copyright @copyright{} 1993 Massachusetts Institute of Technology
+Copyright @copyright{} 1993-94 Massachusetts Institute of Technology
This is Edition @value{EDITION}, last updated @value{UPDATED}, of
@cite{@value{TITLE}}.
@page
@vskip 0pt plus 1filll
-Copyright @copyright{} 1993 Massachusetts Institute of Technology
+Copyright @copyright{} 1993-94 Massachusetts Institute of Technology
This material was developed by the Scheme project at the Massachusetts
Institute of Technology, Department of Electrical Engineering and Computer
x
y)
-(define position-x (slot-accessor 'x))
-(define position-y (slot-accessor 'y))
-(define set-position-x! (slot-modifier 'x))
-(define set-position-y! (slot-modifier 'y))
+(define position-x (slot-accessor <position> 'x))
+(define position-y (slot-accessor <position> 'y))
+(define set-position-x! (slot-modifier <position> 'x))
+(define set-position-y! (slot-modifier <position> 'y))
(define-method initialize-instance ((position <position>) x y)
(set-position-x! position x)
@lisp
@group
-(define (slot-accessor-method slot)
- (make-method (list (slot-class slot))
- (let ((accessor (slot-accessor (slot-name slot))))
- (lambda (call-next-method instance)
- (accessor instance)))))
+(define (slot-accessor-method class name)
+ (make-leaf-method (list class) (slot-accessor class name)))
(define (slot-value instance name)
((slot-accessor name) instance))
@end group
@end lisp
-@deffn Procedure slot-accessor name
+@deffn Procedure slot-accessor class name
Returns a procedure of one argument which is an accessor for the slot
-@var{name}; @var{name} may be either a symbol or a slot descriptor. The
-argument to the returned procedure must be an instance. When the
-procedure is called, it returns the contents of the slot @var{name} in
-that instance. If the given instance does not have a slot of that name,
-or if the slot is not initialized, an error is signalled.
+@var{name} in @var{class}; @var{name} may be either a symbol or a slot
+descriptor. The argument to the returned procedure must be an instance
+of @var{class}. When the procedure is called, it returns the contents
+of the slot @var{name} in that instance. If the given instance does not
+have a slot of that name, or if the slot is not initialized, an error is
+signalled.
@end deffn
-@deffn Procedure slot-modifier name
+@deffn Procedure slot-modifier class name
Returns a procedure of two arguments which is a modifier for the slot
-@var{name}; @var{name} may be either a symbol or a slot descriptor. The
-first argument to the returned procedure must be an instance, and the
-second argument may be any object. When the procedure is called, it
-modifies the slot @var{name} in the instance to contain the second
-argument. If the given instance does not have a slot of that name, an
-error is signalled.
+@var{name} in @var{class}; @var{name} may be either a symbol or a slot
+descriptor. The first argument to the returned procedure must be an
+instance of @var{class}, and the second argument may be any object.
+When the procedure is called, it modifies the slot @var{name} in the
+instance to contain the second argument. If the given instance does not
+have a slot of that name, an error is signalled.
@end deffn
-@deffn Procedure slot-initpred name
+@deffn Procedure slot-initpred class name
Returns a procedure of one argument which is an ``initialized?''@:
-predicate for the slot @var{name}; @var{name} may be either a symbol or
-a slot descriptor. The argument to the returned procedure must be an
-instance. When the procedure is called, it returns @code{#t} if the
-slot @var{name} in that instance is initialized, otherwise it returns
-@code{#f}. If the given instance does not have a slot of that name, an
-error is signalled.
+predicate for the slot @var{name} in @var{class}; @var{name} may be
+either a symbol or a slot descriptor. The argument to the returned
+procedure must be an instance of @var{class}. When the procedure is
+called, it returns @code{#t} if the slot @var{name} in that instance is
+initialized, otherwise it returns @code{#f}. If the given instance does
+not have a slot of that name, an error is signalled.
@end deffn
-@deffn Procedure slot-accessor-method slot
-Returns an accessor method for @var{slot}. This method has one required
-argument, an instance, and the specializer for that argument is the
-@code{slot-class} of @var{slot}. When invoked, the method returns the
-contents of the slot specified by @var{slot} in the instance. However,
-if that slot is not initialized, an error is signalled instead.
+@deffn Procedure slot-accessor-method class name
+Returns an accessor method for the slot @var{name} in @var{class}. This
+method has one required argument, an instance of @var{class}, and the
+specializer for that argument is @var{class}. When invoked, the method
+returns the contents of the slot specified by @var{name} in the
+instance. However, if that slot is not initialized, an error is
+signalled instead.
@end deffn
-@deffn Procedure slot-modifier-method slot
-Returns a modifier method for @var{slot}. This method has two required
-arguments, an instance and an object. The specializer for the first
-argument is the @code{slot-class} of @var{slot}; the second argument is
-not specialized. When invoked, the method stores the second argument in
-the slot specified by @var{slot} in the instance.
+@deffn Procedure slot-modifier-method class name
+Returns a modifier method for slot @var{name} in @var{class}. This
+method has two required arguments, an instance of @var{class} and an
+object. The specializer for the first argument is @code{class}; the
+second argument is not specialized. When invoked, the method stores the
+second argument in the slot specified by @var{name} in the instance.
@end deffn
-@deffn Procedure slot-initpred-method slot
-Returns an ``initialized?''@: predicate method for @var{slot}. This
-method has one required argument, an instance, and the specializer for
-that argument is the @code{slot-class} of @var{slot}. When invoked, the
-method returns @code{#t} if the slot specified by @var{slot} is
-initialized in the instance; otherwise it returns @code{#f}.
+@deffn Procedure slot-initpred-method class name
+Returns an ``initialized?''@: predicate method for slot @var{name} in
+@var{class}. This method has one required argument, an instance of
+@var{class}, and the specializer for that argument is @code{class}.
+When invoked, the method returns @code{#t} if the slot specified by
+@var{name} is initialized in the instance; otherwise it returns
+@code{#f}.
@end deffn
@deffn Procedure slot-value instance name
method procedure, as is the case when a generic procedure is called.
When this occurs it is said that the method is invoked or called.
+A leaf-method object is a special kind of method object that is faster
+to invoke than a regular method object. It gains this speed by
+sacrificing the ``call-next-method'' capability of regular methods (see
+below). Note that the @code{define-method} and @code{method} special
+forms will generate leaf-method objects automatically whenever the
+method body does not contain a free reference to
+@code{call-next-method}.
+
@deffn Syntax define-method generic-procedure lambda-list body @dots{}
Defines a method of @var{generic-procedure}. @var{Lambda-list} is like
the parameter list of a @code{lambda} special form, except that the
@end quotation
@end deffn
+@deffn Procedure make-leaf-method specializers procedure
+Creates and returns a new leaf method object. @var{Specializers} must
+be a non-null list of class objects. @var{Procedure} should accept the
+same number of arguments as the generic procedure to which this method
+will be added; @var{procedure} will not be passed a ``call-next-method''
+procedure argument.
+@end deffn
+
@node Record Classes, , Methods, Language
@subsection Record Classes
@end deffn
@deffn Procedure method-procedure method
-Returns the procedure of @var{method}.
+Returns the procedure of @var{method}. If this is a regular method, the
+returned procedure is the procedure that was passed to
+@code{make-method} when @var{method} was constructed. If this is a leaf
+method, the returned procedure is one that was specially constructed
+when @code{make-leaf-method} was called.
+@end deffn
+
+@deffn Procedure leaf-method-procedure leaf-method
+Returns the procedure of @var{leaf-method}. This is the procedure that
+was passed to @code{make-leaf-method} as an argument when
+@var{leaf-method} was constructed.
@end deffn
@node Slot Reflectives, , Method Reflectives, Reflective Operations
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