Thank You Ian Sharp

On July 16th, one of the most influential founders of what we today refer to as the “array language community” died peacefully, a few months after being diagnosed with lung cancer (link: Toronto Globe and Mail).

Ian Patrick Sharp

In 1964, Ian Patrick Sharp formed I.P.Sharp Associates (IPSA), together with six colleagues who were made redundant when Ferranti-Packard closed its computer division in Toronto, Canada. As Ian explains in a wonderful interview that was recorded in 1984 (link: Snake Island website), he was approached by people who wanted to recruit the whole team. Instead, he decided to form a company, since the team obviously had significant value.

The company was involved in the first APL implementation at IBM (APL\360). Subsequently, IBM allowed them to modify and enhance the system, and built a timesharing service that became known as SHARP APL. Roger Moore was a co-founder of IPSA and, in addition to being responsible for the supervisor that made SHARP APL a superior timesharing system, Roger was the chief architect of IPSANET, one of the worlds first packet switched networks.

In the late 1970s the combination of APL and IPSANET was revolutionary, and IPSA quickly attracted business from global corporate clients who used SHARP APL for e-mail, reporting and analytics, and a rapidly-growing collection of financial timeseries data – all completely new technologies at the time. In particular, the transmission of data over telephone lines changed the world. Ian had many absurd encounters with telecom monopolies who tried to protect old business models or profit from the new technology (link: archive.org).

A Stylised Map of the I.P.Sharp Associates APL Time-Sharing Network

Ian’s management style perfectly matched – and drove – the revolutionary technologies. As Ian explains so eloquently and humorously in the interview, IPSA recruited talented people without necessarily having specific tasks in mind. Ian set the tone and direction and then let people get on with it, moving around in the background to get a sense of how things were going and making adjustments without ever making a fuss. IPSA was a fantastic place to work and attracted a wonderfully diverse (in the most modern sense of the word) collection of smart people who developed revolutionary tools, helped a lot of customers, had a lot of fun, and made money.

Ultimately, IPSA was creative, problem-oriented and customer-driven to the extent that it failed to respond to fundamental changes in the market in time. At the end of the 1980s the timesharing revenues suddenly faded, and the company was acquired by Reuters for its timeseries databases and more or less disappeared overnight. However, IPSA had acted as a fantastic breeding ground for technology and talent for a quarter century, and there are hundreds of people who fondly and gratefully remember Ian for the way that he allowed them all to grow.

I don’t think it is a coincidence that so many of the active array language organisations have key players who were once IPSA employees (some of them appearing in more than one place thanks to relationships forged a very long time ago 😊).

  • Jsoftware: Roger Hui, Eric Iverson, Chris Burke, Ken Iverson
  • Kx: Arthur Whitney, Simon Garland, Stephen Taylor, Chris Burke
  • Dyalog: Gitte Christensen, Morten Kromberg, Roger Hui, Brian Becker, Dan Baronet
  • Snake Island Research: Robert Bernecky

As always, Roger has collected anecdotes about IPSA, Ian and other people who worked there, which you can find on jsoftware.com/papers/SharpQA.htm.

My Own IPSA Story

In 1978, my dad was moving out of an apartment in Oslo. At the same time, XEROX insisted that IPSA open an office in Oslo to support their international business, and several Canadians arrived there. I helped move some furniture and, sensing a keen interest and real excitement in programming, the IPSA Oslo team offered me a free account to play with APL timesharing, if I was interested. I effectively became a piece of furniture in the IPSA office after school, and had keys to the office so I could come and go as I pleased. After a year or so, they started throwing me bits of real work to do and paying me for my time. I think I was 17 at the time.

In addition to working as an APL consultant and tool builder, one of the things I did in my spare time was to write a tool for myself that would compare the entire contents of the e-mail directory with its state at the end of the previous week. Since IPSA was 100% managed by e-mail groups, this allowed me to know instantly when a new office was opened, a significant new project was started, and, of course, when new employees joined the company. By using this technique of harvesting e-mail addresses and sending unsolicited e-mail when an interesting project or person joined, I found my future partner both at home and the office – Gitte, the current CEO of Dyalog Ltd – only about 500km away in the IPSA Copenhagen branch.

I spent about a decade at IPSA and, after its sudden disappearance, Gitte and I have been trying to recreate the IPSA atmosphere in every team that we have been a member of. In a very real sense, I owe not only my career but almost everything of value about my life to Ian Sharp and the warm and welcoming company that he created.

Thank You, Ian!

Welcome Rodrigo Girão Serrão

The story of how Rodrigo got his first internship at Dyalog is, in his opinion, a textbook example of serendipity. As 2020 started, Rodrigo began actively participating in an online code golf community, where people try to solve programming challenges in as few bytes of code as possible. Whilst his golfing skills were possibly lacking, the challenges he posted were usually well accepted. Posting many challenges meant Rodrigo got exposed to answers in all sorts of programming languages, from C, Java, Python and JavaScript, to Jelly, 05AB1E, Husk…and APL. Because of the context and the aspect of it, Rodrigo first thought APL was one of those “esolangs” and not a serious programming language.

Rodrigo’s fascination with APL led him to start frequenting The APL Orchard chatroom, where a small number of brilliant people convened to discuss all things APL. Here he met Adám Brudzewsky, who was keen on teaching APL to newcomers, and so began Rodrigo’s journey to learn APL.

His interest in APL kept growing, and he found it to be a simple and expressive language that also incorporated his affinity with mathematics. One day, while lurking in The APL Orchard, Adám asked Rodrigo if he would be interested in taking an intern position at Dyalog…a few emails later it was established that Rodrigo would work as a part-time intern at Dyalog during the Summer of 2020. This enabled Dyalog to make the most of Rodrigo’s skills in teaching and technical writing, and meant Rodrigo could indulge his passion for sharing knowledge about mathematics and programming while still finishing his MSc in Applied Mathematics. After his internship, Rodrigo took some time to complete his MSc thesis before returning to Dyalog to finish what he had started and hopefully to take part in many other interesting projects. When he is not working for Dyalog, Rodrigo may be found leading a Portuguese APL meetup, writing a blog post for his website (mathspp.com), or maybe leading a workshop or course. Other than working, Rodrigo likes to spend time with his loved ones, read fantasy books, eat chocolate, and watch silly comedy movies.

Welcome Shuhao Yang

Image

Shuhao joined Dyalog straight after he completed his Master’s degree in quantum computing, which happened to be during the second COVID-related lockdown in the UK. This has given him a quite unusual experience of starting a career as he has yet to meet a single member of the Dyalog team face to face! Shuhao obtained his Bachelor’s degree in mathematics – although he was interested in computer science, he studied mathematics as a way of looking for the root of CS and computing. He has broad interests across different software including Matlab, Python and LaTeX and has developed a solid knowledge on C++.

Shuhao enjoys the romantic theories in computer science and always wanted to work in one of the summit areas of CS – compilers, graphics and operating systems. He’s very happy that he now has the opportunity to work on the Dyalog APL interpreter.

The APL Orchard

If you have not already been there, I highly recommend visiting the APL Orchard (apl.chat). Adám Brudzewsky originally started this chat room on Stack Exchange to teach and answer questions, including many successful introductory sessions to people who wanted to learn APL. Since then, it has become an extremely active discussion forum, with a very wide range of interesting conversations, from regularly helping more newcomers get started with APL to theoretical discussions about the design of future array languages that will improve APL and perhaps compete against it some day.

Interested in APL?

One of Adám’s infamous invitations to a personalised APL introduction

Several of the most active participants have written their own APL implementations and some are working on array languages that are quite different from APL. It is a lively crowd, generating lots of thought-provoking discussions that feel a lot like the big arguments that I remember witnessing between Iverson, Benkard, Bernecky, Falkoff, Trenchard More and others at APL conferences back in the days when the APL language was still being born.

The participants include a mix of current, past and future employees of Dyalog Ltd, and it is a source of much useful inspiration for future work on our product and healthy challenges to conventional wisdom, so I try to spend some time there every day.

APL Orchard Stats

APL Orchard message statistics. The bottom contains the all-time total number of participants and messages.

To the New APLers

The Orchard is sometimes a challenging environment for a Dyalog CTO. Many of the bright young minds with computer science backgrounds that arrive here are quick to latch on to the fact that many things about APL go against the grain of what they were taught at university, and that a few of the design decisions made during the 55 years since the first APL implementation were questionable and could do with rationalisation. There is a constant barrage of complaints that we are not working hard to “fix” the things that they consider to be wrong about APL. This is, of course, how things should be when youthful enthusiasm meets us “fossils”; I fully understand many of the points made and actually agree with quite a few of them.

It is sometimes hard work having to repeatedly defend why Dyalog does not do things like just fix index origin at 0 and give the customers a few years to refactor their code. The implication is often that we are incompetent, and occasionally there is the insinuation that we are driven by questionable commercial motives like trying to get rich by locking the customers in and then doing a minimum of work.

Evolution, not Revolution

In my opinion, a large part of the value of our product rests on the fact that our customers can do things like read new legislation that affects the way their code needs to compute something, write code to deal with it before lunch, and then expect the code to keep working without changes until the law changes again, which might be in four years (depending on which country you live in), or in a few decades, after the current programmers have retired. Meanwhile, the code might need to move from the mainframe via UNIX and DOS to Microsoft Windows or macOS and then on to Linux in the cloud, and whatever comes after that.

APLers actually do enjoy refactoring code *if* it is in order to meet new challenges in the markets that they serve with products based on APL or compute better results. Our duty is to make this easy for them. On the other hand, there is no business value in refactoring code because we decided to change the way the language works, due to theoretical considerations – and it is our duty to protect them from that.

Breaking changes to Dyalog APL are quite simply not an option, at least not if users have to take immediate action. When we accidentally make a breaking change despite our best efforts not to, there is much wailing and gnashing of teeth, and we have to drop everything to fix it. That doesn’t mean we can’t make significant changes to how things work, but we must take an evolutionary approach, where the old way continues to work until everyone who needs it has moved on, possibly controlled by (sometimes undocumented) switches, like the one that forces APL to continue to give a DOMAIN ERROR on ¯1*0.5 to protect legacy code that relies on trapping the error in certain financial calculations.

Over the past decade, we have been able to move almost all of our user base from a 32-bit product with a fixed “alphabet” of 256 characters to using 64-bit APL with full Unicode support, in many cases without requiring any changes to application code. The stragglers are mostly major clients with support contracts that justify the additional cost of continuing to support the “legacy” version of the product until they are eventually able to move on. Once the Raspberry Pi stabilises as a 64-bit platform, we may finally be able to completely retire 32-bit Dyalog APL. I estimate that the “Classic” (non-Unicode) version probably needs to exist for another 5-10 years.

The next big challenges for us are to ensure that code can be moved to macOS and Linux (and “the cloud”) with a minimum of changes, and that both new and existing users have ways to integrate both new and legacy APL code nicely with modern source code management systems and continuous integration pipelines.

Existing Customers First

Our first priority at Dyalog is to support our existing clients and make sure that they remain competitive in their respective marketplaces.

Some contributors to the APL Orchard have suggested that this prevents us from being able to attract new users, which they believe can only happen if we quickly fix some of the “warts” in the language, or add some even more powerful language constructs.

First of all: not a single person who I consider to be a real prospect for writing substantial new application code in APL has brought up a single one of these issues as a reason why they might not want to adopt APL.

Secondly: if we do not first ensure our own financial stability, we will not have the resources to perform evolution, let alone revolution. For example, our investment in the creation of the APL Orchard, the APL Wiki, and the creation of new training materials for potential new users of APL, all depend on this.

As they say in the pre-flight briefing: put on your own oxygen mask before helping others.

Third: it is my very strong conviction that making breaking changes would violate the trust that exists between Dyalog and its customers, and I would personally consider it to be unethical. This may sound like a radical position, but it is one that I would expect to resonate with the younger generation. My personal motivation for working on software stems from witnessing the value that is created when people use software that I have helped create. Once someone starts using “my” product (and they continue to indicate that it is important to them by paying for support), I have an obligation to protect them from harm, if it is in my power.

Conclusion

APL is Fun
Old timers: If you are looking for some interesting discussions about current and future array languages, to help some newcomers, and maybe learn some new tricks yourself, I suggest that you head over to the APL Orchard and dive in, it is a lot of fun! You might want to check out apl.wiki/APL_Orchard, which has some helpful hints and tips, before you start.

New folks: I hope that this explanation of some of the philosophy that drives our work at Dyalog helps to explain some of the decisions that we make and that you find to be puzzling. I fully recognise that it is hard to imagine that a software company might have customer relationships that started before you were born 😊.

There are a couple of other topics that I should possibly also explain my views on, such as the dilemma of whether APL is a Notation or a Programming Language, and why Dyalog APL is not open source, but this post is very long already. Depending on the response I get to this post, I may return to that in the future.

Dyalog ’20 – Recordings Now Available

We are happy to announce that the full set of recordings from Dyalog ’20 online is now available. So if you missed the all or any of the talks, or would like to revisit one of the presentations, head over to https://dyalog.tv/Dyalog20!

It was disappointing not to be enjoying Portuguese food and drink with you all in Olhão. On the other hand, it was wonderful to be able to share our plans and user stories with so many people who would not normally be able to travel to one of our user meetings. According to the statistics, we had about twice the usual number of attendees, and Dyalog ’20 may have been the largest gathering of APL users in the last quarter century!

We learned that we need to invest in better microphones and find better solutions for chat both during and between the presentations, but in general we feel that the online format worked so well that we are making plans to run similar events in the future, even if international travel restrictions should ease and we are able to meet many of you face to face in Portugal this coming October. We are still thinking about the details, but it is likely that we will host an online meeting each spring with a focus on new users of Dyalog APL, while the autumn (fall) meeting will continue to provide experienced users with the usual “deep dive”.

We are also planning to offer workshops and other training sessions at other times of the year, and continue the regular series of webinars. Travel restrictions are helping to accelerate our plans to provide a steadily increasing quantity of online material. If there is sufficient interest, I am willing to expand my talk on Docker containers into a half-day “Bring Your Own Application” workshop early in 2021. If you would like to attend this workshop, or you have ideas for other topics for webinars, workshops or talks at future user meetings, please write to usermeeting@dyalog.com and tell us about it!

Welcome Ron Murray

Ron flying in 2003

Ron Murray is a recent addition to the Dyalog team, with a long history in the APL community. He first encountered APL/360 in 1969 and was hooked. He used it as the basis for teaching Computer Science courses for the Hampton, Virginia High Schools. Then, working with other APL pioneers, he wrote several APL applications and contributed to five different APL implementations at The Computer Company, STSC, Burroughs, Data Resources, and Analogic Corporation.

From 1986 until 2019 he left the world of APL to develop software on Microcomputers for Microsoft and Amazon, where he contributed to various development projects for Windows, OS/2, NT, Visual Basic, Encarta, and a variety of projects within the Microsoft Research Division as well the Developer Relations Group. He also contributed to the scalability and reliability of the Amazon transaction accounting system and the Windows Azure Archival Storage System.

He also ran an Aviation business for several years at the Tacoma Narrows airport, and started an internet television company with three friends. Together they learned a lot about crawling the web using machine learning, categorizing videos by their subject matters and quality, as well as constructing interactive user interfaces on IOS devices.

During all that non-APL work he continued to use APL as a tool of thought for organizing, analyzing, and clarifying the work that needed to be done.

Since July of 2020 he’s been applying the many non-APL things he’s learned to help extend and improve the Dyalog APL systems and their interactions with the rest of the computing world.

He points out that Windows 95, which is now 25 years old is about half as old as the APL/360 release!