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The World Wide Web Consortium has launched a new specification called "XProc," which provides a standard framework for composing XML processes.  It streamlines the automation, sequencing, and management of complex XML processes, the standards body said.  The "XML Pipeline Language" spec was developed to provide a framework for managing enterprise-level business processes.

Building a dynamic PHP site requires you to understand how CRUD (create, read, update, delete) functions work. There are a variety of ways to implement these functions include databases, and most commonly through mySQL.  With these functions you can add new entries to the database (registration), view existing entries (retrieve users or fields), update the entries to your table or delete users (who may unsubscribe or permanently delete their accounts.) For a user account based sites, these functions are essential for keeping your user and information database up to date.

Erlang allows for massively scalable concurrency, often with millions of lightweight, thread-like components known as actors. Unfortunately, using Erlang requires rewriting all of your legacy code into a rather esoteric language. But there are other options, such as the little known CCR platform that was developed by .NET's robotics department. Actor based languages such as Erlang are able to achieve high degrees of parallelism by using the Actor model. Under this model the fundamental unit of concurrency is not a thread or fiber, but rather something much smaller. Known as a "process" in Erlang, each unit of concurrency has a base overhead of about 1200 bytes on a 32-bit system. By comparison, a thread on the Windows operating system defaults to 1 MB just for the stack, additional space is also needed for bookkeeping and thread local storage. Because they are so lightweight, an application can spawn literally millions of processes simultaneously.

If you need a quick reference guide for the UML notation, check one of the following, IMHO, gret UML cheat sheets (in no particular order):

Did you know you can use F# type providers to access thousands of statistical packages from R, with auto-complete and documentation? Those of you into data analysis will be aware of the use of the R system by statisticians and other data workers. The F# community and BlueMountain Capital have created a type provider for F#-R interop which embeds all installed R packages directly into F#, with intellisense.  See the  example below. 

First, right off the top here: Scala has true blue Java-like null; any reference may be null. Its presence muddies the water quite a bit. But since Beust's article explicitly talks about Haskell he's clearly not talking about that aspect of Scala because Haskell doesn't have null. I'll get back to Scala's null at the end but for now pretend it doesn't exist.Second, just to set the record straight: "Option" has roots in programming languages as far back as ML. Both Haskell's "Maybe" and Scala's "Option" (and F#'s "Option" and others) trace their ancestry to it.

Dave Megginson (who drove the development of the SAX API that will be familiar to many XML developers who use Java) recently wrote Java is dead. Java stood out as a programming language (though not as a platform) in that Sun had refused to standardize it through an independent and reputable standards organization (a lot of the hard work had been done in one attempt to put it through ECMA and one to put it through ISO, both times Sun pulled out and eventually made their highly unsatisfactory JCP Java Community Process system.) Without the ability to alter Java significantly in ways that might go against their druthers, Java suffered two major forks (Microsoft's J++ then its C#, and IBM's SWT) where significant players disagreed with a major component (the graphics library). Java succeeded in middleware, and but failed to take advantage of the rise of browsers on the deskop: their HTML parser was great for the middle 1990s but was deliberately neglected to the point of being unusable: it is hard not to see this as a deliberate attempt by Sun to leave the browser market to its friends and enemies. I really liked Java, and bet my company on it (in a sense): I would not do that today.

In ASP.NET development, F# also offers productivity advantages over VB and C#.  F# is different because it is statically checked and type-safe.  It addresses weaknesses in ASP.NET development like untyped values, complex form construction, and using strings for IDs and method names that connect markup with code-behind (class-files).  Writing a web application in F# on the WebSharper platform can be less-time consuming if a developer is not great at writing web apps in JavaScript.  Through WebSharper, developers can write a web app using a large subset of F# and .NET core libraries and then just let WebSharper map the code to JavaScript.  WebSharper can integrate with ASP.NET applications, but it is different from the standard approach because it builds applications from miniature web pages called "pagelets".  The pagelets correspond to functions on the client-side and they are automatically translated into JavaScript.   WebSharper supports a wide range of JavaScript libraries, making it easy for developers to optimize their code in whatever way they choose.  jQuery, qooxdoo, Flapjax, and Yahoo UI are all supported by WebSharper.  The leap from F# to JavaScript is manageable because both are functional languages that support lambda expressions and closures.  Another unique part of WebSharper is a "formlet".  A formlet is a special pagelet that provides form functionality.  Formlets in Web Sharper run and validate on the client, submitting their result to a either a client- or a server-side callback.

At the beginning of the '90s there were 26 published methods on object-orientation, most with its own notation with its own set of icons. It was in this environment that UML was born. Although Grady Booch, Jim Rumbaugh, and Ivar Jacobson initiated the design of what became UML, many other contributors (including Steve Cook) quickly joined the effort and the Object Management Group (OMG) launched the result. UML quickly made most other methods -- along with their own notations, obsolete -- UML eventually became the standard we had hoped for, and toolbuilders and practitioners rapidly adopted the new approach.

Google today launched an "early preview" of Dart, a programming language the company hopes will help Web application programmers overcome shortcomings of JavaScript that Google itself feels acutely.

ScalaModules is an open source project aimed at providing fluent support for OSGi to Scala developers. It takes advantage of Scala's infix operator notation, higher order functions, and implicit conversions. ScalaModules transparently uses the Scala compiler to wrap an OSGi BundleContext with its own RichBundleContext model. This general technique is not unusual for creating DSLs in mainstream languages. Sean McDirmid uses similar tricks for his C# Bling library for WPF, except that Bling must overcome the lack of C# offering comparable extensions to Scala.

In this interview Spotty Bowles, a tester on the VB Compiler team, shows us a couple of new language features: Array and Collection Initializers. He gives us insight into how they are implemented in the compiler and best practices on how to use them in our code. Additionally, he discusses how to extend Collection Initializers with your own extension methods.

We consider the problem of specifying combinations of data structures with complex sharing in a manner that is both declarative and results in provably correct code. In our approach, abstract data types are specified using relational algebra and functional dependencies. We describe a language of decompositions that permit the user to specify different concrete representations for relations, and show that operations on concrete representations soundly implement their relational specification. It is easy to incorporate data representations synthesized by our compiler into existing systems, leading to code that is simpler, correct by construction, and comparable in performance to the code it replaces.