Lambda the Ultimate

Tim Bray reports about half of the JVM language summit. Among the things he discusses are Clojure, PHP and JVM/CLR cross-pollination.

You can read the docs and download the C++ source here.

V8 is supposedly the main added value of Chrome, the newly announced Google browser.

Our discussion of the Chrome announcement enumerates some of the features of V8.

The proceedings of the 2008 LLVM Developers' Meeting have been posted. The presentations included some overviews of various LLVM subsystems and internals and a few projects targeting the LLVM. Previous meeting's proceedings are also available.

Phil Windley Technometria podcast is dedicated to the Google Web Toolkit. The guest on the show is Bruce Johnson a Tech Lead of GWT.

The show is very good, and more technical than usual. Many themes that are near and dear to LtU are discussed. Here are some pointers:

Bruce talks at length about the advantages of compiling from Java to JS, many of which arise from Java's static typing. He mainly talks about optimizations, but also about how static typing helps with tools in general (IDEs etc.). This was a subject of long and stormy debates here in the past.

The advantages, from a software engineering standpoint, of building in Java vs. JS are discussed. This is directly related to the ongoing discusison here on the new programming-in-the-large features added to JS2. I wonder if someone will write a compiler from Java/GWT to JS2 at some point, which will enable projects to move to JS2 and jump ship on Java all together.

Bruce mentions that since JS isn't class-based, and thus doesn't directly support the OO style many people are used to, there are many ways of translating common OO idioms into JS. This is, of course, the same type of dilemma the Scheme community has about many high level features. Cast as a question on OOP support the questions becomes is it better to provide language constructs that allow various libraries to add OO support in different ways, or to provide language support for a specific style. The same can be asked about a variety of features and programming styles, of course.

Finally, Bruce mentions that as far as he knows no one thought about something like GWT before they did. Well, I for one, and I don't think I was the only one, talked many times (probably on LtU) about Javascript as a VM/assembly language of the browser, clearly thinking about JS as a target language. I admint I wasn't thinking aobut compiling Java... But then, I am not into writing Java, so why would I think about Java as the source language...

Charles Nutter:

If you are interested in the future of non-Java languages on the JVM, you should be on this list. Yes, we talk about a lot of JVM lanuage implementation challenges, we discuss compilers and stack frames and call-site optimizations, but we also talk about features peripheral to language implementation like package indexing and retrofitting Java 5+ code. We need your help.

Abstract Interface Types in GNAT: Conversions, Discriminants, and C++. Javier Miranda and Edmond Schonberg.

Ada 2005 Abstract Interface Types provide a limited and practical form of multiple inheritance of specifications. In this paper we cover the following aspects of their implementation in the GNAT compiler: interface type conversions, the layout of variable sized tagged objects with interface progenitors, and the use of the GNAT compiler for interfacing with C++ classes with compatible inheritance trees.

The addition of interface types, of the type found in Java, to Ada2005 presented compiler writers with an implementation challenge. This is a third paper in a series describing the implementation of interfaces in the GNAT Ada compiler (an earlier paper dealt with synchronized interfaces, an interesting special case).

The present paper deals mainly with issues caused by interface type conversions, and the related data layout issues. Of special interest is section 6 which shows how to write a C++/Ada multi-language program, in which method calls can be dispatched across language boundaries. Handling the multiple inheritance in the C++ code in this example is possible because the base classes have only pure virtual functions.

I'm back... Going through my RSS feeds, two items caught my attention:

Tim Bray: Charles Nutter and Thomas Enebo, better known as “The JRuby Guys”, are joining Sun this month.

Jon Udell: Why argue about dynamic versus static languages when you can use both? Which discusses, among other things, why the first three versions of the IronPython compiler were written in Python, but today it's written in C#.

A report on Gilad Bracha's presentation at Lang.NET 2006 entitled "Dynamically Typed Languages on the Java Platform".

We discussed several of the ideas mentioned, but I think we should continue to follow this story.

There are a variety of reasons why we haven’t implemented continuations in the JVM. High on the list: continuations are costly to implement, and they might reek havoc with Java SE security model. These arguments are pragmatic and a tad unsatisfying. If a feature is really important, shouldn’t we just bite the bullet?

Many here will not like the answer.

This issue was discussed here mnay time, of course, but I think it is of interest to know what the people at Sun are thinking...

Tim Bray's response is also worth checking out, if only for the sake of this sound bite: The worst AJAX apps are like bad Nineties VB.

The .NET Programming Languages And Compilers Symposium: Lang .NET 2006

Seattle, Washington, United States, August 1-3, 2006

Call for contributions

Lang .NET 2006 is a forum for discussion of programming languages, managed execution environments, compilers, multi-language libraries, and integrated development environments. It provides an excellent opportunity for programming language implementers and researchers from both industry and academia to meet and share their knowledge, experience, and suggestions for future research and development in the area of programming languages.

Lang.NET 2006 will be held from August 1-3 on the Microsoft corporate campus in Redmond immediately after OSCON 2006 in Portland.

The conference program will focus on the pragmatics and experience of designing languages, implementing compilers, and building language tools that target managed execution platforms such as the .NET CLR and other implementations of the ECMA CLI. That is, on how to get real programming tools into the hands of real programmers to solve real problems, and on how researchers and practitioners can learn from each other to make this happen.

If you are a language designer, compiler writer, or tool builder in industry or academia, Lang.NET 2006 is a unique opportunity to directly interact with the architects of Microsoft language platforms. Microsoft language technologist will be very active participants in the conference but at least 50% of the program is reserved for presentations by non-Microsoft employees. Each day is concluded with a panel debate. In the evenings there will be ample opportunity for networking during the social events and dinners.

The program committee invites 1-page abstracts of experience reports, demonstrations and presentations related to programming language and compilers to be given at the symposium. There will be two types of talks:

• 10 minute lightning talks
• 30 minute regular talks

We are looking for lively presentations that are provocative, stimulating and educational. Submit your proposals at here.

Areas of interest include but are not limited to:

• Dynamic languages and scripting
• AJAX and ATLAS
• Domain specific languages
• Functional languages
• Object-oriented and aspect-oriented programming
• Web-services and mobile code
• Libraries
• Language-Integrated Query (LINQ)
• Compiler frameworks
• Garbage collection
• JIT compilation
• Visual Programming
• Success and failure stories
• Non-standard language features and implementation techniques
• Tools and IDE support

Dates

Submissions due	May 15, 2006
Notification of acceptance	June 1, 2006

Conference chair

Thottam Sriram, Microsoft

Program committee

• Erik Meijer, Microsoft  (program chair)
• Allen Wirfs-Brock, Microsoft
• Martin Maly, Microsoft
• Amanda Silver, Microsoft
• Brian Tyler, National Instruments
• Paul Austin, National Instruments
• Stephen Gennard, Microfocus
• Robert Sales, Microfocus
• Rene Rodriguez, ASNA
• Roger Andrews, Synergex
• Kasper Osterbye, IT University Copenhagen