Simplifying Javascript with Concatenation-Based Prototype Inheritance Tampereen Teknillinen Yliopisto
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Ercatons and Organic Programming: Say Good-Bye to Planned Economy
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Dagstuhl Research Online Publication Server Ercatons and Organic Programming: Say Good-Bye to Planned Economy Oliver Imbusch, Falk Langhammer and Guido von Walter Living Pages Research GmbH Kolosseumstrasse 1a, 80469 Munich, Germany {flabes|falk|guido}@livis.com ABSTRACT 1. Motivation Organic programming (OP) is our proposed and already We are going to present an alternative way to develop soft- emerging programming model which overcomes some of ware. We followed this idea starting from some general the limitations of current practice in software development observations all the way down to a reference implementa- in general and of object-oriented programming (OOP) in tion which was then used in projects of sufficient size. This particular. Ercatons provide an implementation of the makes us trust into the initial idea to the point that we may model. In some respects, OP is less than a (new) program- now be obsessed by it. Let us start by sharing some of the ming language, in others, it is more. An “ercato machine” general observations. implements the ideas discussed and has been used to vali- We start with this trivial anecdote. date the concepts described here. “One morning, we noticed some workers tile our office's Organic programming is centered around the concept of a backyard. The day before, piles of square tiles had been true “Thing”. A thing in an executing software system is delivered and the workers now seemed to make good prog- bound to behave the way an autonomous object does in our ress covering the backyard's middle section. -
Dynamic, Instance-Based, Object-Oriented Programming in Max/Msp Using Open Sound Control Message Delegation
Proceedings of the International Computer Music Conference 2011, University of Huddersfield, UK, 31 July - 5 August 2011 DYNAMIC, INSTANCE-BASED, OBJECT-ORIENTED PROGRAMMING IN MAX/MSP USING OPEN SOUND CONTROL MESSAGE DELEGATION Adrian Freed John MacCallum Andrew Schmeder CNMAT CNMAT CNMAT Dept. of Music Dept. of Music Dept. of Music UC Berkeley, CA 94709 UC Berkeley, CA 94709 UC Berkeley, CA 94709 [email protected] [email protected] [email protected] ABSTRACT oriented programming in Max–presumably because of the hegemony of statically-typed class-based object- A new media programming style is introduced that oriented programming invented in Simula (1962) and brings efficient run-time polymorphism, functional and still active in Objective-C, C++ and Java. instance-based object-oriented programming to Max/MSP and related visual dataflow languages. In 2007 the first author developed a suite of Max/MSP Examples are presented to illustrate new, unusual and patches, called “o.” (pronounced “Oh dot”). These were effective applications of the approach of using OSC specifically designed to exploit generic programming messages for object representations and data flow for (pioneered in Ada in 1980) to simplify and teach gesture method delegation. signal processing in physical computing contexts. This early prototype explored the use of OSC (Sections 2-3 1. INTRODUCTION of this paper), ad-hoc polymorphism and delegation Open Sound Control (OSC) was originally designed as a (Sections 4 and 6) for dynamic class-less object- message-passing format to facilitate exchange of control orientated programming (OOP) based on his experience parameters between programs on different computers developing music programs in prototype-based OOP across a network. -
Programming in Lua, Second Edition by Roberto Ierusalimschy
Programming ROBERTO IERUSALIMSCHY in Lua 2nd edition Lua.org Last update: Wed Jan 13 12:07:33 UTC 2010 Programming in Lua Property of Ian Bloss <[email protected]> Property of Ian Bloss <[email protected]> Programming in Lua Second Edition Roberto Ierusalimschy PUC-Rio, Brazil Lua.org Rio de Janeiro Property of Ian Bloss <[email protected]> Programming in Lua, Second Edition by Roberto Ierusalimschy ISBN 85-903798-2-5 Copyright c 2006, 2003 by Roberto Ierusalimschy. All rights reserved. The author can be contacted at [email protected]. Book cover and illustrations by Dimaquina. Lua logo design by Alexandre Nako. Typesetting by the author using LATEX. Although the author used his best efforts preparing this book, he assumes no responsibility for errors or omissions, or for any damage that may result from the use of the information presented here. All product names mentioned in this book are trademarks of their respective owners. CIP – Biblioteca do Departamento de Informatica,´ PUC-Rio Ierusalimschy, Roberto I22 Programming in Lua / Roberto Ierusalimschy. – 2nd ed. – Rio de Janeiro, 2006. xviii, 308 p. : 25 cm. Includes index. ISBN 85-903798-2-5 1. Lua (Programming language). I. Title. 005.133 – dc20 Property of Ian Bloss <[email protected]> to Ida, Noemi, and Ana Lucia Property of Ian Bloss <[email protected]> Property of Ian Bloss <[email protected]> Contents Preface xiii I The Language 1 1 Getting Started 3 1.1 Chunks 4 1.2 Some Lexical Conventions 5 1.3 Global Variables 6 1.4 The Stand-Alone Interpreter 7 2 Types and Values -
Regular Expressions
Regular Expressions A regular expression describes a language using three operations. Regular Expressions A regular expression (RE) describes a language. It uses the three regular operations. These are called union/or, concatenation and star. Brackets ( and ) are used for grouping, just as in normal math. Goddard 2: 2 Union The symbol + means union or or. Example: 0 + 1 means either a zero or a one. Goddard 2: 3 Concatenation The concatenation of two REs is obtained by writing the one after the other. Example: (0 + 1) 0 corresponds to f00; 10g. (0 + 1)(0 + ") corresponds to f00; 0; 10; 1g. Goddard 2: 4 Star The symbol ∗ is pronounced star and means zero or more copies. Example: a∗ corresponds to any string of a’s: f"; a; aa; aaa;:::g. ∗ (0 + 1) corresponds to all binary strings. Goddard 2: 5 Example An RE for the language of all binary strings of length at least 2 that begin and end in the same symbol. Goddard 2: 6 Example An RE for the language of all binary strings of length at least 2 that begin and end in the same symbol. ∗ ∗ 0(0 + 1) 0 + 1(0 + 1) 1 Note precedence of regular operators: star al- ways refers to smallest piece it can, or to largest piece it can. Goddard 2: 7 Example Consider the regular expression ∗ ∗ ((0 + 1) 1 + ")(00) 00 Goddard 2: 8 Example Consider the regular expression ∗ ∗ ((0 + 1) 1 + ")(00) 00 This RE is for the set of all binary strings that end with an even nonzero number of 0’s. -
Technical Standard COBOL Language
Technical Standard COBOL Language NICAL H S C T A E N T D A R D [This page intentionally left blank] X/Open CAE Specification COBOL Language X/Open Company, Ltd. December 1991, X/Open Company Limited All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the copyright owners. X/Open CAE Specification COBOL Language ISBN: 1 872630 09 X X/Open Document Number: XO/CAE/91/200 Set in Palatino by X/Open Company Ltd., U.K. Printed by Maple Press, U.K. Published by X/Open Company Ltd., U.K. Any comments relating to the material contained in this document may be submitted to X/Open at: X/Open Company Limited Apex Plaza Forbury Road Reading Berkshire, RG1 1AX United Kingdom or by Electronic Mail to: [email protected] X/Open CAE Specification (1991) Page : ii COBOL Language Contents COBOL LANGUAGE Chapter 1 INTRODUCTION 1.1 THE X/OPEN COBOL DEFINITION 1.2 HISTORY OF THIS DOCUMENT 1.3 FORMAT OF ENTRIES 1.3.1 Typographical Conventions 1.3.2 Terminology Chapter 2 COBOL DEFINITION 2.1 GENERAL FORMAT FOR A SEQUENCE OF SOURCE PROGRAMS 2.2 GENERAL FORMAT FOR NESTED SOURCE PROGRAMS 2.2.1 Nested-Source-Program 2.3 GENERAL FORMAT FOR IDENTIFICATION DIVISION 2.4 GENERAL FORMAT FOR ENVIRONMENT DIVISION 2.5 GENERAL FORMAT FOR SOURCE-COMPUTER-ENTRY 2.6 GENERAL FORMAT FOR OBJECT-COMPUTER-ENTRY 2.7 GENERAL FORMAT FOR SPECIAL-NAMES-CONTENT 2.8 GENERAL FORMAT FOR FILE-CONTROL-ENTRY 2.8.1 -
The Self-4.0 User Interface: Manifesting a System-Wide Vision of Concreteness, Uniformity, and Flexibility
The Self-4.0 User Interface: Manifesting a System-wide Vision of Concreteness, Uniformity, and Flexibility Randall B. Smith, John Maloney†, and David Ungar Sun Microsystems Laboratories 2550 Casey Ave. MTV29-116 Mountain View, CA 94043 [email protected], [email protected], [email protected] Abstract ming systems seem pretty awkward and abstruse by comparison. Manipulating programs is hard, while manipulating Of course it would be a difficult and dubious objects in the physical world is often easy. Several attributes of the physical world help make it compre- effort to literally replicate the physical world in the hensible and manipulable: concreteness, uniformity, computer. But embodying key elements of our physi- and flexibility. The Self programming system cal reality might bring benefits to the computing attempts to apply these attributes to the world within experience. The rise of object-oriented programming the computer. The semantics of the language, the may be viewed as the outcome of an effort to allow efficiency and fidelity of its implementation, and the computers to more directly model physical systems. architecture of its user interface conspire to make the experience of constructing programs in Self immedi- However, even object-oriented programming sys- ate and tangible. We describe the mechanisms used tems don’t really give you anything like that real- to achieve this goal, and illustrate those mechanisms world sense of obvious straightforwardness, that within the context of an extended programming task. sense of immediacy. We believe something more can be found by reexamining the essence of physical sys- tems. I. Introduction Three important characteristics of physical reality that are not truly present in most program- There is a satisfying directness in working ming systems, even object-oriented ones, are con- with physical objects. -
CMPSCI 250 Lecture
CMPSCI 250: Introduction to Computation Lecture #29: Proving Regular Language Identities David Mix Barrington 6 April 2012 Proving Regular Language Identities • Regular Language Identities • The Semiring Axioms Again • Identities Involving Union and Concatenation • Proving the Distributive Law • The Inductive Definition of Kleene Star • Identities Involving Kleene Star • (ST)*, S*T*, and (S + T)* Regular Language Identities • In this lecture and the next we’ll use our new formal definition of the regular languages to prove things about them. In particular, in this lecture we’ll prove a number of regular language identities, which are statements about languages where the types of the free variables are “regular expression” and which are true for all possible values of those free variables. • For example, if we view the union operator + as “addition” and the concatenation operator ⋅ as “multiplication”, then the rule S(T + U) = ST + SU is a statement about languages and (as we’ll prove today) is a regular language identity. In fact it’s a language identity as regularity doesn’t matter. • We can use the inductive definition of regular expressions to prove statements about the whole family of them -- this will be the subject of the next lecture. The Semiring Axioms Again • The set of natural numbers, with the ordinary operations + and ×, forms an algebraic structure called a semiring. Earlier we proved the semiring axioms for the naturals from the Peano axioms and our inductive definitions of + and ×. It turns out that the languages form a semiring under union and concatenation, and the regular languages are a subsemiring because they are closed under + and ⋅: if R and S are regular, so are R + S and R⋅S. -
Some Aspects of Semirings
Appendix A Some Aspects of Semirings Semirings considered as a common generalization of associative rings and dis- tributive lattices provide important tools in different branches of computer science. Hence structural results on semirings are interesting and are a basic concept. Semi- rings appear in different mathematical areas, such as ideals of a ring, as positive cones of partially ordered rings and fields, vector bundles, in the context of topolog- ical considerations and in the foundation of arithmetic etc. In this appendix some algebraic concepts are introduced in order to generalize the corresponding concepts of semirings N of non-negative integers and their algebraic theory is discussed. A.1 Introductory Concepts H.S. Vandiver gave the first formal definition of a semiring and developed the the- ory of a special class of semirings in 1934. A semiring S is defined as an algebra (S, +, ·) such that (S, +) and (S, ·) are semigroups connected by a(b+c) = ab+ac and (b+c)a = ba+ca for all a,b,c ∈ S.ThesetN of all non-negative integers with usual addition and multiplication of integers is an example of a semiring, called the semiring of non-negative integers. A semiring S may have an additive zero ◦ defined by ◦+a = a +◦=a for all a ∈ S or a multiplicative zero 0 defined by 0a = a0 = 0 for all a ∈ S. S may contain both ◦ and 0 but they may not coincide. Consider the semiring (N, +, ·), where N is the set of all non-negative integers; a + b ={lcm of a and b, when a = 0,b= 0}; = 0, otherwise; and a · b = usual product of a and b. -
Comparative Programming Languages CM20253
We have briefly covered many aspects of language design And there are many more factors we could talk about in making choices of language The End There are many languages out there, both general purpose and specialist And there are many more factors we could talk about in making choices of language The End There are many languages out there, both general purpose and specialist We have briefly covered many aspects of language design The End There are many languages out there, both general purpose and specialist We have briefly covered many aspects of language design And there are many more factors we could talk about in making choices of language Often a single project can use several languages, each suited to its part of the project And then the interopability of languages becomes important For example, can you easily join together code written in Java and C? The End Or languages And then the interopability of languages becomes important For example, can you easily join together code written in Java and C? The End Or languages Often a single project can use several languages, each suited to its part of the project For example, can you easily join together code written in Java and C? The End Or languages Often a single project can use several languages, each suited to its part of the project And then the interopability of languages becomes important The End Or languages Often a single project can use several languages, each suited to its part of the project And then the interopability of languages becomes important For example, can you easily -
The Evolution of Lua
The Evolution of Lua Roberto Ierusalimschy Luiz Henrique de Figueiredo Waldemar Celes Department of Computer Science, IMPA–Instituto Nacional de Department of Computer Science, PUC-Rio, Rio de Janeiro, Brazil Matematica´ Pura e Aplicada, Brazil PUC-Rio, Rio de Janeiro, Brazil [email protected] [email protected] [email protected] Abstract ing languages offer associative arrays, in no other language We report on the birth and evolution of Lua and discuss how do associative arrays play such a central role. Lua tables it moved from a simple configuration language to a versatile, provide simple and efficient implementations for modules, widely used language that supports extensible semantics, prototype-based objects, class-based objects, records, arrays, anonymous functions, full lexical scoping, proper tail calls, sets, bags, lists, and many other data structures [28]. and coroutines. In this paper, we report on the birth and evolution of Lua. We discuss how Lua moved from a simple configuration Categories and Subject Descriptors K.2 [HISTORY OF language to a powerful (but still simple) language that sup- COMPUTING]: Software; D.3 [PROGRAMMING LAN- ports extensible semantics, anonymous functions, full lexical GUAGES] scoping, proper tail calls, and coroutines. In §2 we give an overview of the main concepts in Lua, which we use in the 1. Introduction other sections to discuss how Lua has evolved. In §3 we re- late the prehistory of Lua, that is, the setting that led to its Lua is a scripting language born in 1993 at PUC-Rio, the creation. In §4 we relate how Lua was born, what its original Pontifical Catholic University of Rio de Janeiro in Brazil. -
Theme and Variations on the Concatenation Product
Theme and variations on the concatenation product Jean-Eric´ Pin1⋆ LIAFA, University Paris-Diderot and CNRS, France. Abstract. The concatenation product is one of the most important op- erations on regular languages. Its study requires sophisticated tools from algebra, finite model theory and profinite topology. This paper surveys research advances on this topic over the last fifty years. The concatenation product plays a key role in two of the most important results of automata theory: Kleene’s theorem on regular languages [23] and Sch¨utzen- berger’s theorem on star-free languages [60]. This survey article surveys the most important results and tools related to the concatenation product, including connections with algebra, profinite topology and finite model theory. The paper is organised as follows: Section 1 presents some useful algebraic tools for the study of the concatenation product. Section 2 introduces the main definitions on the product and its variants. The classical results are summarized in Section 3. Sections 4 and 5 are devoted to the study of two algebraic tools: Sch¨utzenberger products and relational morphisms. Closure properties form the topic of Section 6. Hierarchies and their connection with finite model theory are presented in Sections 7 and 8. Finally, new directions are suggested in Section 9. 1 The instruments This section is a brief reminder on the algebraic notions needed to study the con- catenation product: semigroups and semirings, syntactic ordered monoids, free profinite monoids, equations and identities, varieties and relational morphisms. More information can be found in [1–3,18,35,42,45]. 1.1 Semigroups and semirings If S is a semigroup, the set P(S) of subsets of S is also a semiring, with union as addition and multiplication defined, for every X, Y ∈P(S), by XY = {xy | x ∈ X,y ∈ Y } In this semiring, the empty set is the zero and for this reason, is denoted by 0. -
8. Objects and Prototypes
8. Objects and Prototypes Oscar Nierstrasz Based on material by Adrian Lienhard All examples can be found in the usual git repo, [email protected]:lectures-pl-examples as well as online: http://scg.unibe.ch/download/lectures/pl-examples/JavaScript/ Roadmap > Class- vs. prototype-based languages > Objects, properties and methods > Delegation > Constructors > Closures > Snakes and Ladders with prototypes > The Good, the Bad and the Ugly 2 References > JavaScript: The Definitive Guide, D. Flanagan, O’Reilly, 5th edition > JavaScript: The Good Parts, D. Crockford, O’Reilly > JavaScript Guide & Reference, Mozilla Developer Center, http:// developer.mozilla.org/en/docs/JavaScript > Using Prototypical Objects to Implement Shared Behavior in Object Oriented Systems, H. Lieberman, OOPSLA’86 > ECMAScript Language Specification — 5th edition, http://www.ecma- international.org/publications/standards/Ecma-262.htm > ECMAScript 6 features —http://es6-features.org/#Constants 3 Roadmap > Class- vs. prototype-based languages > Objects, properties and methods > Delegation > Constructors > Closures > Snakes and Ladders with prototypes > The Good, the Bad and the Ugly 4 Class-based vs. Prototype-based languages Class-based: Prototype-based: > Classes share methods and > No classes, only objects define common properties > Objects define their own > Inheritance along class chain properties and methods > Instances have exactly the > Objects delegate to their properties and behavior prototype(s) defined by their class > Any object can be the prototype > Structure typically cannot be of another object changed at runtime Prototype-based languages unify objects and classes 6 In class-based languages, classes may (e.g., in Smalltalk) or may not be (e.g., in Java) be first-class objects.