Functional Programming in C++11
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Building Great Interfaces with OOABL
Building great Interfaces with OOABL Mike Fechner Director Übersicht © 2018 Consultingwerk Ltd. All rights reserved. 2 Übersicht © 2018 Consultingwerk Ltd. All rights reserved. 3 Übersicht Consultingwerk Software Services Ltd. ▪ Independent IT consulting organization ▪ Focusing on OpenEdge and related technology ▪ Located in Cologne, Germany, subsidiaries in UK and Romania ▪ Customers in Europe, North America, Australia and South Africa ▪ Vendor of developer tools and consulting services ▪ Specialized in GUI for .NET, Angular, OO, Software Architecture, Application Integration ▪ Experts in OpenEdge Application Modernization © 2018 Consultingwerk Ltd. All rights reserved. 4 Übersicht Mike Fechner ▪ Director, Lead Modernization Architect and Product Manager of the SmartComponent Library and WinKit ▪ Specialized on object oriented design, software architecture, desktop user interfaces and web technologies ▪ 28 years of Progress experience (V5 … OE11) ▪ Active member of the OpenEdge community ▪ Frequent speaker at OpenEdge related conferences around the world © 2018 Consultingwerk Ltd. All rights reserved. 5 Übersicht Agenda ▪ Introduction ▪ Interface vs. Implementation ▪ Enums ▪ Value or Parameter Objects ▪ Fluent Interfaces ▪ Builders ▪ Strong Typed Dynamic Query Interfaces ▪ Factories ▪ Facades and Decorators © 2018 Consultingwerk Ltd. All rights reserved. 6 Übersicht Introduction ▪ Object oriented (ABL) programming is more than just a bunch of new syntax elements ▪ It’s easy to continue producing procedural spaghetti code in classes ▪ -
Functional Javascript
www.it-ebooks.info www.it-ebooks.info Functional JavaScript Michael Fogus www.it-ebooks.info Functional JavaScript by Michael Fogus Copyright © 2013 Michael Fogus. All rights reserved. Printed in the United States of America. Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472. O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions are also available for most titles (http://my.safaribooksonline.com). For more information, contact our corporate/ institutional sales department: 800-998-9938 or [email protected]. Editor: Mary Treseler Indexer: Judith McConville Production Editor: Melanie Yarbrough Cover Designer: Karen Montgomery Copyeditor: Jasmine Kwityn Interior Designer: David Futato Proofreader: Jilly Gagnon Illustrator: Robert Romano May 2013: First Edition Revision History for the First Edition: 2013-05-24: First release See http://oreilly.com/catalog/errata.csp?isbn=9781449360726 for release details. Nutshell Handbook, the Nutshell Handbook logo, and the O’Reilly logo are registered trademarks of O’Reilly Media, Inc. Functional JavaScript, the image of an eider duck, and related trade dress are trademarks of O’Reilly Media, Inc. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and O’Reilly Media, Inc., was aware of a trade‐ mark claim, the designations have been printed in caps or initial caps. While every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. -
Pattern Matching
Functional Programming Steven Lau March 2015 before function programming... https://www.youtube.com/watch?v=92WHN-pAFCs Models of computation ● Turing machine ○ invented by Alan Turing in 1936 ● Lambda calculus ○ invented by Alonzo Church in 1930 ● more... Turing machine ● A machine operates on an infinite tape (memory) and execute a program stored ● It may ○ read a symbol ○ write a symbol ○ move to the left cell ○ move to the right cell ○ change the machine’s state ○ halt Turing machine Have some fun http://www.google.com/logos/2012/turing-doodle-static.html http://www.ioi2012.org/wp-content/uploads/2011/12/Odometer.pdf http://wcipeg.com/problems/desc/ioi1211 Turing machine incrementer state symbol action next_state _____ state 0 __1__ state 1 0 _ or 0 write 1 1 _10__ state 2 __1__ state 1 0 1 write 0 2 _10__ state 0 __1__ state 0 _00__ state 2 1 _ left 0 __0__ state 2 _00__ state 0 __0__ state 0 1 0 or 1 right 1 100__ state 1 _10__ state 1 2 0 left 0 100__ state 1 _10__ state 1 100__ state 1 _10__ state 1 100__ state 1 _10__ state 0 100__ state 0 _11__ state 1 101__ state 1 _11__ state 1 101__ state 1 _11__ state 0 101__ state 0 λ-calculus Beware! ● think mathematical, not C++/Pascal ● (parentheses) are for grouping ● variables cannot be mutated ○ x = 1 OK ○ x = 2 NO ○ x = x + 1 NO λ-calculus Simplification 1 of 2: ● Only anonymous functions are used ○ f(x) = x2+1 f(1) = 12+1 = 2 is written as ○ (λx.x2+1)(1) = 12+1 = 2 note that f = λx.x2+1 λ-calculus Simplification 2 of 2: ● Only unary functions are used ○ a binary function can be written as a unary function that return another unary function ○ (λ(x,y).x+y)(1,2) = 1+2 = 3 is written as [(λx.(λy.x+y))(1)](2) = [(λy.1+y)](2) = 1+2 = 3 ○ this technique is known as Currying Haskell Curry λ-calculus ● A lambda term has 3 forms: ○ x ○ λx.A ○ AB where x is a variable, A and B are lambda terms. -
Automating Testing with Autofixture, Xunit.Net & Specflow
Design Patterns Michael Heitland Oct 2015 Creational Patterns • Abstract Factory • Builder • Factory Method • Object Pool* • Prototype • Simple Factory* • Singleton (* this pattern got added later by others) Structural Patterns ● Adapter ● Bridge ● Composite ● Decorator ● Facade ● Flyweight ● Proxy Behavioural Patterns 1 ● Chain of Responsibility ● Command ● Interpreter ● Iterator ● Mediator ● Memento Behavioural Patterns 2 ● Null Object * ● Observer ● State ● Strategy ● Template Method ● Visitor Initial Acronym Concept Single responsibility principle: A class should have only a single responsibility (i.e. only one potential change in the S SRP software's specification should be able to affect the specification of the class) Open/closed principle: “Software entities … should be open O OCP for extension, but closed for modification.” Liskov substitution principle: “Objects in a program should be L LSP replaceable with instances of their subtypes without altering the correctness of that program.” See also design by contract. Interface segregation principle: “Many client-specific I ISP interfaces are better than one general-purpose interface.”[8] Dependency inversion principle: One should “Depend upon D DIP Abstractions. Do not depend upon concretions.”[8] Creational Patterns Simple Factory* Encapsulating object creation. Clients will use object interfaces. Abstract Factory Provide an interface for creating families of related or dependent objects without specifying their concrete classes. Inject the factory into the object. Dependency Inversion Principle Depend upon abstractions. Do not depend upon concrete classes. Our high-level components should not depend on our low-level components; rather, they should both depend on abstractions. Builder Separate the construction of a complex object from its implementation so that the two can vary independently. The same construction process can create different representations. -
Lambda Calculus and Functional Programming
Global Journal of Researches in Engineering Vol. 10 Issue 2 (Ver 1.0) June 2010 P a g e | 47 Lambda Calculus and Functional Programming Anahid Bassiri1Mohammad Reza. Malek2 GJRE Classification (FOR) 080299, 010199, 010203, Pouria Amirian3 010109 Abstract-The lambda calculus can be thought of as an idealized, Basis concept of a Turing machine is the present day Von minimalistic programming language. It is capable of expressing Neumann computers. Conceptually these are Turing any algorithm, and it is this fact that makes the model of machines with random access registers. Imperative functional programming an important one. This paper is programming languages such as FORTRAN, Pascal etcetera focused on introducing lambda calculus and its application. As as well as all the assembler languages are based on the way an application dikjestra algorithm is implemented using a Turing machine is instructed by a sequence of statements. lambda calculus. As program shows algorithm is more understandable using lambda calculus in comparison with In addition functional programming languages, like other imperative languages. Miranda, ML etcetera, are based on the lambda calculus. Functional programming is a programming paradigm that I. INTRODUCTION treats computation as the evaluation of mathematical ambda calculus (λ-calculus) is a useful device to make functions and avoids state and mutable data. It emphasizes L the theories realizable. Lambda calculus, introduced by the application of functions, in contrast with the imperative Alonzo Church and Stephen Cole Kleene in the 1930s is a programming style that emphasizes changes in state. formal system designed to investigate function definition, Lambda calculus provides a theoretical framework for function application and recursion in mathematical logic and describing functions and their evaluation. -
Designpatternsphp Documentation Release 1.0
DesignPatternsPHP Documentation Release 1.0 Dominik Liebler and contributors Jul 18, 2021 Contents 1 Patterns 3 1.1 Creational................................................3 1.1.1 Abstract Factory........................................3 1.1.2 Builder.............................................8 1.1.3 Factory Method......................................... 13 1.1.4 Pool............................................... 18 1.1.5 Prototype............................................ 21 1.1.6 Simple Factory......................................... 24 1.1.7 Singleton............................................ 26 1.1.8 Static Factory.......................................... 28 1.2 Structural................................................. 30 1.2.1 Adapter / Wrapper....................................... 31 1.2.2 Bridge.............................................. 35 1.2.3 Composite............................................ 39 1.2.4 Data Mapper.......................................... 42 1.2.5 Decorator............................................ 46 1.2.6 Dependency Injection...................................... 50 1.2.7 Facade.............................................. 53 1.2.8 Fluent Interface......................................... 56 1.2.9 Flyweight............................................ 59 1.2.10 Proxy.............................................. 62 1.2.11 Registry............................................. 66 1.3 Behavioral................................................ 69 1.3.1 Chain Of Responsibilities................................... -
Purity in Erlang
Purity in Erlang Mihalis Pitidis1 and Konstantinos Sagonas1,2 1 School of Electrical and Computer Engineering, National Technical University of Athens, Greece 2 Department of Information Technology, Uppsala University, Sweden [email protected], [email protected] Abstract. Motivated by a concrete goal, namely to extend Erlang with the abil- ity to employ user-defined guards, we developed a parameterized static analysis tool called PURITY, that classifies functions as referentially transparent (i.e., side- effect free with no dependency on the execution environment and never raising an exception), side-effect free with no dependencies but possibly raising excep- tions, or side-effect free but with possible dependencies and possibly raising ex- ceptions. We have applied PURITY on a large corpus of Erlang code bases and report experimental results showing the percentage of functions that the analysis definitely classifies in each category. Moreover, we discuss how our analysis has been incorporated on a development branch of the Erlang/OTP compiler in order to allow extending the language with user-defined guards. 1 Introduction Purity plays an important role in functional programming languages as it is a corner- stone of referential transparency, namely that the same language expression produces the same value when evaluated twice. Referential transparency helps in writing easy to test, robust and comprehensible code, makes equational reasoning possible, and aids program analysis and optimisation. In pure functional languages like Clean or Haskell, any side-effect or dependency on the state is captured by the type system and is reflected in the types of functions. In a language like ERLANG, which has been developed pri- marily with concurrency in mind, pure functions are not the norm and impure functions can freely be used interchangeably with pure ones. -
Design Patterns for QA Automation Anton Semenchenko
Design Patterns for QA Automation Anton Semenchenko CONFIDENTIAL 1 Agenda, part 1 (general) 1. Main challenges 2. Solution 3. Design Patterns – the simplest definition 4. Design Patterns language – the simplest definition 5. Encapsulation – the most important OOP principle CONFIDENTIAL 2 Agenda, part 2 (main patterns) 1. Page Element 2. Page Object 3. Action CONFIDENTIAL 3 Agenda, part 3 (less popular patterns) 1. Flow (Fluent Interface) – Ubiquitous language – Key word driven – Behavior Driven Development (BDD) 2. Domain Specific Language (DSL) – Flow 3. Navigator (for Web) CONFIDENTIAL 4 Agenda, part 4 (take away points) 1. “Rules” and principles 2. A huge set of useful links 3. A huge set of examples CONFIDENTIAL 5 2 main challenges in our every day work (interview experience) 1. Pure design 2. Over design CONFIDENTIAL 6 Solution 1. Find a balance CONFIDENTIAL 7 Design Patterns – the simplest definition 1. Elements (blocks) of reusable object-oriented software; 2. The re-usable form of a solution to a design problem; CONFIDENTIAL 8 Design Patterns – as a language 1. Design patterns that relate to a particular field (for example QA Automation) is called a pattern language 2. Design Patterns language gives a common terminology for discussing the situations specialists are faced with: – “The elements of this language are entities called patterns”; – “Each pattern describes a problem that occurs over and over again in our (QA Automation) environment”; – “Each pattern describes the core of the solution to that problem, in such a way that you can use this solution a million times over, without ever doing it the same way twice!” CONFIDENTIAL 9 Design Patterns for QA Automation 1. -
Drools Expert User Guide
Drools Expert User Guide Version 6.0.0.CR2 by The JBoss Drools team [http://www.jboss.org/drools/team.html] ....................................................................................................................................... vii 1. Introduction ................................................................................................................. 1 1.1. Artificial Intelligence ............................................................................................ 1 1.1.1. A Little History ......................................................................................... 1 1.1.2. Knowledge Representation and Reasoning ................................................ 2 1.1.3. Rule Engines and Production Rule Systems (PRS) .................................... 3 1.1.4. Hybrid Reasoning Systems (HRS) ............................................................ 5 1.1.5. Expert Systems ........................................................................................ 8 1.1.6. Recommended Reading ........................................................................... 9 1.2. Why use a Rule Engine? .................................................................................. 12 1.2.1. Advantages of a Rule Engine ................................................................. 13 1.2.2. When should you use a Rule Engine? ..................................................... 14 1.2.3. When not to use a Rule Engine .............................................................. 15 1.2.4. Scripting -
Deep Dive Into Programming with CAPS HMPP Dev-Deck
Introduction to HMPP Hybrid Manycore Parallel Programming Московский государственный университет, Лоран Морен, 30 август 2011 Hybrid Software for Hybrid Hardware • The application should stay hardware resilient o New architectures / languages to master o Hybrid solutions evolve: we don‟t want to redo the work each time • Kernel optimizations are the key to get performance o An hybrid application must get the best of its hardware resources 30 август 2011 Москва - Лоран Морен 2 Methodology to Port Applications Methodology to Port Applications Hotspots Parallelization •Optimize CPU code •Performance goal •Exhibit Parallelism •Validation process •Move kernels to GPU •Hotspots selection •Continuous integration Define your Port your Hours to Days parallel application Days to Weeks project on GPU GPGPU operational Phase 1 application with known potential Phase 2 Tuning Optimize your GPGPU •Exploit CPU and GPU application •Optimize kernel execution •Reduce CPU-GPU data transfers Weeks to Months 30 август 2011 Москва - Лоран Морен 4 Take a decision • Go • Dense hotspot • Fast GPU kernels • Low CPU-GPU data transfers • Midterm perspective: Prepare to manycore parallelism • No Go o Flat profile o GPU results not accurate enough • cannot validate the computation o Slow GPU kernels • i.e. no speedup to be expected o Complex data structures o Big memory space requirement 30 август 2011 Москва - Лоран Морен 5 Tools in the Methodology Hotspots Parallelization • Profiling tools Gprof, Kachegrind, Vampir, Acumem, ThreadSpotter •HMPP Workbench •Debugging -
Efficient Engineering and Execution of Pipe-And-Filter Architectures
Efficient Engineering and Execution of Pipe-and-Filter Architectures Dissertation M.Sc. Christian Wulf Dissertation zur Erlangung des akademischen Grades Doktor der Ingenieurwissenschaften (Dr.-Ing.) der Technischen Fakultät der Christian-Albrechts-Universität zu Kiel eingereicht im Jahr 2019 1. Gutachter: Prof. Dr. Wilhelm Hasselbring Christian-Albrechts-Universität zu Kiel 2. Gutachter: Prof. Dr. Steffen Becker Universität Stuttgart Datum der mündlichen Prüfung: 19. Juli 2019 ii Zusammenfassung Pipe-and-Filter (P&F) ist ein wohlbekannter und häufig verwendeter Archi- tekturstil. Allerdings gibt es unseres Wissens nach kein P&F-Framework, das beliebige P&F-Architekturen sowohl modellieren als auch ausführen kann. Beispielsweise unterstützen die Frameworks FastFlow, StreamIT and Spark nicht mehrere Input- und Output-Ströme pro Filter, sodass sie kei- ne Verzweigungen modellieren können. Andere Frameworks beschränken sich auf sehr spezielle Anwendungsfälle oder lassen die Typsicherheit zwi- schen zwei miteinander verbundenen Filtern außer Acht. Außerdem ist eine effiziente parallele Ausführung von P&F-Architekturen weiterhin eine Herausforderung. Obwohl einige vorhandene Frameworks Filter parallel ausführen können, gibt es noch viel Optimierungspotential. Leider besit- zen die meisten Frameworks kaum Möglichkeiten, die einzig vorhandene Ausführungsstrategie ohne großen Aufwand anzupassen. In dieser Arbeit präsentieren wir unser generisches und paralleles P&F- Framework TeeTime. Es kann beliebige P&F-Architekturen sowohl model- lieren als auch ausführen. Gleichzeitig ist es offen für Modifikationen, um mit dem P&F-Stil zu experimentieren. Zudem erlaubt es, Filter effizient und parallel auf heutigen Multi-core-Systemen auszuführen. Umfangreiche Laborexperimente zeigen, dass TeeTime nur einen sehr geringen und in gewissen Fällen gar keinen zusätzlichen Laufzeit-Overhead im Vergleich zu Implementierungen ohne P&F-Abstraktionen erfordert. -
The Quantum IO Monad Thorsten Altenkirch and Alexander S
1 The Quantum IO Monad Thorsten Altenkirch and Alexander S. Green School of Computer Science, The University of Nottingham Abstract The Quantum IO monad is a purely functional interface to quantum programming implemented as a Haskell library. At the same time it provides a constructive semantics of quantum programming. The QIO monad separates reversible (i.e. unitary) and irreversible (i.e. prob- abilistic) computations and provides a reversible let operation (ulet), allowing us to use ancillas (auxiliary qubits) in a modular fashion. QIO programs can be simulated either by calculating a probability distribu- tion or by embedding it into the IO monad using the random number generator. As an example we present a complete implementation of Shor’s algorithm. 1.1 Introduction We present an interface from a pure functional programming language, Haskell, to quantum programming: the Quantum IO monad, and use it to implement Shor’s factorisation algorithm. The implementation of the QIO monad provides a constructive semantics for quantum programming, i.e. a functional program which can also be understood as a mathematical model of quantum computing. Actually, the Haskell QIO library is only a first approximation of such a semantics, we would like to move to a more expressive language which is also logically sound. Here we are thinking of a language like Agda (Norell (2007)), which is based on Martin L¨of’s Type Theory. We have already investigated this approach of functional specifications of effects in a classical context (Swierstra and Altenkirch (2007, 2008); Swierstra (2008)). At the same 1 2 Thorsten Altenkirch and Alexander S.