ReasonML is a new, type-safe, functional language that compiles to efficient, readable JavaScript. ReasonML interoperates with existing JavaScript libraries and works especially well with React, one of the most popular front-end frameworks. Learn how to take advantage of the power of a functional language while keeping the flexibility of the whole JavaScript ecosystem. Move beyond theory and get things done faster and more reliably with ReasonML today. ReasonML is a new syntax for OCaml, a battle-tested programming language used in industry for over 20 years. Designed to be familiar to JavaScript programmers, ReasonML code compiles to highly readable JavaScript. With ReasonML, you get OCaml's powerful functional programming features: a strong static type system with an excellent type inference engine, pattern matching, and features for functional programming with immutable variables. ReasonML also allows flexibility with opt-in side effects, mutation, and object-oriented programming. ReasonML hits the sweet spot between the pure theoretical world and the laissez-faire approach of JavaScript. Start using ReasonML's powerful type system as you learn the essentials of the language: variables and arithmetic operations. Gain expressive power as you write functions with named parameters and currying. Define your own data types, and integrate all these capabilities into a simple web page. Take advantage of ReasonML's functional data structures with map and reduce functions. Discover new ways to write algorithms with ReasonML's recursion support. Interoperate with existing JavaScript libraries with bindings, and write reactive web applications using ReasonML in tandem with React. Reinforce concepts with examples that range from short, tightly focused functions to complete programs, and practice your new skills with exercises in each chapter.With ReasonML, harness the awesome power of a functional language while retaining the best features of JavaScript to produce concise, fast, type-safe programs. What You Need: You'll need to have node.js (version 10.0 or above) and npm (version 5.6 or above). Once you install the bs-platform package and fire up a text editor, you're ready to go. (There are plugins for many popular editors that will make editing easier.)

ReasonML, also known as Reason, is a new syntax and toolchain for OCaml that was created by Facebook and is meant to be approachable for web developers. Although OCaml has several resources, most of them are from the perspective of systems development. This book, alternatively, explores Reason from the perspective of web development.

A fast paced guide for JavaScript developers for writing safe, fast, and reusable code by leveraging ResaonML's strong static type system Key FeaturesReduce code errors with the power of type systemsEmploy static typechecking and genericity to promote code reuse and consistencyUnderstand functional programming which is the foundation of type-driven developmentBook Description Type-driven development is an approach that uses a static type system to achieve results including safety and efficiency. Types are used to express relationships and other assumptions directly in the code, and these assumptions are enforced by the compiler before the code is run. Learn Type-Driven Development covers how to use these type systems to check the logical consistency of your code. This book begins with the basic idea behind type-driven development. You’ll learn about values (or terms) and how they contrast with types. As you progress through the chapters, you’ll cover how to combine types and values inside modules and build structured types out of simpler ones. You’ll then understand how to express choices or alternatives directly in the type system using variants, polymorphic variants, and generalized algebraic data types. You’ll also get to grips with sum types, build sophisticated data types from generics, and explore functions that express change in the types of values. In the concluding chapters, you’ll cover advanced techniques for code reuse, such as parametric polymorphism and subtyping. By end of this book, you will have learned how to iterate through a type-driven process of solving coding problems using static types, together with dynamic behavior, to obtain more safety and speed. What you will learnUse static types to capture information, making programs safer and faster Learn ReasonML from experienced type-driven developers Enhance safety by simply using basic types Understand the most important type-driven concepts with simple examples Explore a design space using static typing and find the best way to express your system rules Use static types and dynamic runtime in harmony to write even safer and faster codeWho this book is for If you’re a programmer working with dynamically typed languages and are looking for ways to mitigate production runtime errors, Learn Type-Driven Development is for you. You’ll also find this book helpful if you’re a programmer working with statically typed languages looking for increased safety and improved performance.

htmx is a library that adds logic and server interaction to HTML; you get the effect of using a front-end SPA framework without writing front-end code. Use any server-side programming language and framework to build server applications with endpoints that simply return snippets of HTML. Dynamically update portions of the current web page from HTTP responses. Add interactivity with JavaScript and libraries such Alpine and _hyperscript. Make your apps more secure by escaping user-supplied content and specifying a Content Security Policy. Go beyond basic HTTP requests with WebSockets and server-sent events. The htmx JavaScript library gives you a new way to craft web applications. The htmx approach differs significantly from that of the currently popular single-page application (SPA) frameworks; rather than write a bunch of JavaScript, you simply annotate HTML elements before you send them to the browser. The resulting code is easier to understand and modify, and because it downloads less to the browser and doesn't need JSON creation and parsing, you'll find it performs better, too. Rethink web application design; write code in any language that simply responds to requests with htmx snippets. Dynamically update portions of the current web page directly from the server. Implement common patterns such as lazy loading, input validation, CSS transitions, active search, optimistic updates, pagination, infinite scroll, polling, and click-to-edit. Add interactivity with JavaScript and libraries such as Alpine and _hyperscript. Use the htmx JavaScript API to simplify DOM operations. Make your web apps more secure: escape user-supplied content, use Subresource Integrity hashes, and enforce a Content Security Policy. Go beyond the basic HTTP request/response pattern with WebSockets and server-sent events. Discover a simpler way to implement web applications that emphasizes web fundamentals. What You Need: A modern web browser and the ability to build and run a local HTTP server using the server-side language and framework of your choice. The code examples are fully compatible with htmx 2.0.

Access the power of bare-metal systems programming with Scala Native, an ahead-of-time Scala compiler. Without the baggage of legacy frameworks and virtual machines, Scala Native lets you re-imagine how your programs interact with your operating system. Compile Scala code down to native machine instructions; seamlessly invoke operating system APIs for low-level networking and IO; control pointers, arrays, and other memory management techniques for extreme performance; and enjoy instant start-up times. Skip the JVM and improve your code performance by getting close to the metal. Developers generally build systems on top of the work of those who came before, accumulating layer upon layer of abstraction. Scala Native provides a rare opportunity to remove layers. Without the JVM, Scala Native uses POSIX and ANSI C APIs to build concise, expressive programs that run unusually close to bare metal. Scala Native compiles Scala code down to native machine instructions instead of JVM bytecode. It starts up fast, without the sluggish warm-up phase that's common for just-in-time compilers. Scala Native programs can seamlessly invoke operating system APIs for low-level networking and IO. And Scala Native lets you control pointers, arrays, and other memory layout types for extreme performance. Write practical, bare-metal code with Scala Native, step by step. Understand the foundations of systems programming, including pointers, arrays, strings, and memory management. Use the UNIX socket API to write network client and server programs without the sort of frameworks higher-level languages rely on. Put all the pieces together to design and implement a modern, asynchronous microservice-style HTTP framework from scratch. Take advantage of Scala Native's clean, modern syntax to write lean, high-performance code without the JVM. What You Need: A modern Windows, Mac OS, or Linux system capable of running Docker. All code examples in the book are designed to run on a portable Docker-based build environment that runs anywhere. If you don't have Docker yet, see the Appendix for instructions on how to get it.

Most programming languages contain good and bad parts, but JavaScript has more than its share of the bad, having been developed and released in a hurry before it could be refined. This authoritative book scrapes away these bad features to reveal a subset of JavaScript that's more reliable, readable, and maintainable than the language as a whole—a subset you can use to create truly extensible and efficient code. Considered the JavaScript expert by many people in the development community, author Douglas Crockford identifies the abundance of good ideas that make JavaScript an outstanding object-oriented programming language-ideas such as functions, loose typing, dynamic objects, and an expressive object literal notation. Unfortunately, these good ideas are mixed in with bad and downright awful ideas, like a programming model based on global variables. When Java applets failed, JavaScript became the language of the Web by default, making its popularity almost completely independent of its qualities as a programming language. In JavaScript: The Good Parts, Crockford finally digs through the steaming pile of good intentions and blunders to give you a detailed look at all the genuinely elegant parts of JavaScript, including: Syntax Objects Functions Inheritance Arrays Regular expressions Methods Style Beautiful features The real beauty? As you move ahead with the subset of JavaScript that this book presents, you'll also sidestep the need to unlearn all the bad parts. Of course, if you want to find out more about the bad parts and how to use them badly, simply consult any other JavaScript book. With JavaScript: The Good Parts, you'll discover a beautiful, elegant, lightweight and highly expressive language that lets you create effective code, whether you're managing object libraries or just trying to get Ajax to run fast. If you develop sites or applications for the Web, this book is an absolute must.

Like it or not, JavaScript is everywhere these days—from browser to server to mobile—and now you, too, need to learn the language or dive deeper than you have. This concise book guides you into and through JavaScript, written by a veteran programmer who once found himself in the same position. Speaking JavaScript helps you approach the language with four standalone sections. First, a quick-start guide teaches you just enough of the language to help you be productive right away. More experienced JavaScript programmers will find a complete and easy-to-read reference that covers each language feature in depth. Complete contents include: JavaScript quick start: Familiar with object-oriented programming? This part helps you learn JavaScript quickly and properly. JavaScript in depth: Learn details of ECMAScript 5, from syntax, variables, functions, and object-oriented programming to regular expressions and JSON with lots of examples. Pick a topic and jump in. Background: Understand JavaScript’s history and its relationship with other programming languages. Tips, tools, and libraries: Survey existing style guides, best practices, advanced techniques, module systems, package managers, build tools, and learning resources.