Symbolics Genera was the world's first commercial object-oriented operating system. This paper describes a few interesting aspects of Genera, recounts some experience, and offers advice to designers of future object-oriented systems

Computational reflection makes it easy to solve problems that are otherwise difficult to address in Smalltalk-80, such as the construction of monitors, distributed objects, and futures, and can allow experimentation with new inheritance, delegation, and protection schemes. Full reflection is expensive to implement. However, the ability to override method lookup can bring much of the power of reflection to languages like Smalltalk-80 at no cost in

Introduction The Common Lisp Object System is an object-oriented extension to Common Lisp as defined in Common Lisp: The Language, by Guy L. Steele Jr. It is based on generic functions, multiple inheritance, declarative method combination, and a meta-object protocol. The first two chapters of this specification present a description of the standard Programmer Interface for the Common Lisp Object System. The first chapter contains a description of the concepts of the Common Lisp Object System, and the second contains a description of the functions and macros in the Common Lisp Object System Programmer Interface. The chapter "The Common Lisp Object System Meta-Object Protocol" describes how the Common Lisp Object System can be customized. The fundamental objects of the Common Lisp Object System are classes, instances, generic functions, and methods. A class object determines the structure and behavior of a set of other objects, which are called its instances. Every Common Lisp object is an instance of a class. The class of an object determines the set of operations that can be performed on the object. A generic function is a function whose behavior depends on the classes or identities of the arguments supplied to it. A generic function object contains a set of methods, a lambda-list, a method combination type, and other information. The methods define the class-specific behavior and operations of the generic function; a method is said to specialize a generic function. When invoked, a generic function executes a subset of its methods based on the classes of its arguments. A generic function can be used in the same ways that an ordinary function can be used in Common Lisp; in particular, a generic function can be used as an argument to funcall and apply and can be given a global or a local name. A method is an object that contains a method function, a sequence of parameter speclalizers that specify when the given method is applicable, and a sequence of qualifiers that is used by the method combination facility to distinguish among methods. Each required formal parameter of each method has an associated parameter specializer, and the method will be invoked only on arguments that satisfy its parameter specializers. The method combination facility controls the selection of methods, the order in which they are run, and the values that are returned by the generic function. The Common Lisp Object System offers a default method combination type and provides a facility for declaring new types of method combination.

Introduction The Common Lisp Object System is an object-oriented extension to Common Lisp as defined in Common Lisp: The Language, by Guy L. Steele Jr. It is based on generic functions, multiple in...

This Lisp-based system helps designers get from prototype to product faster. The key is an open architecture and highly integrated development tools.

This 471-page, softcover manual describes the programming language and software environment of the Lisp Machine developed at M.I.T.'s Artificial Intelligence Laboratory over the past 8 years. The Lisp Machine is the result of a successful experiment in computer science: a distributed computing system consisting of a network of powerful 32-bit personal computers, implemented with custom hardware and software as complete, interactive graphical workstations. Each machine consists of a 32-bit computer with 64 megabytes of virtual memory, 1 to 16 megabytes of main memory, 80 megabytes (or larger) disk, 800x900 graphics display (color optional), mouse, keyboard, speaker and 4 million bit/second local network interface, which allows connections to other Lisp Machines, primers and file servers.

Abstract : The object oriented programming style used in the Smalltalk and Actor languages is available in Lisp Machine Lisp, and used by the Lisp Machine software system. It is used to perform generic operations on objects. Part of its implementation is simply a convention in procedure calling style; part is a powerful language feature, called Flavors, for defining abstract objects. This chapter attempts to explain what programming the objects and with message passing means, the various means of implementing these in Lisp Machine Lisp, and when you should use them. It assumes no prior knowledge of any other language.