Languages on Roads Less Taken

Spry Error Handling

Wed, 21 Apr 2021 00:00:00 +0000

Work on Spry continues… in small spurts. :) One thing that I have pushed ahead of me for far too long is error handling. People interested in Spry have been asking about it and yes, I decided to start getting a handle on it.

In fact, I wrote this article last year but forgot to get it done and published!

Error handling is an interesting topic, earlier it wasn’t really much controversy around it but the advent of new techniques (Optionals etc) in combination with languages making… “interesting” choices (I am looking at you Go) has made this subject fairly hot. So what do we want in Spry??

Revisiting Spry

Fri, 05 Jun 2020 00:00:00 +0000

After a period of slower progress I got reignited regarding Spry . So far I have written a lot of articles about Spry, and during this time things have evolved and changed.

So I am now trying to “clean house” on where Spry stands today. This sweep through the old articles is a first step, then I will update the language manual to be 100% in sync with the implementation.

Let’s go through the articles from the beginning!

Writing Arduinobot in Nim

Thu, 26 Oct 2017 00:00:00 +0000

In the eCraft2Learn project which Evothings is participating in we were looking at various ways Nim is an awesome programming language and this article is a whirlwind-copy-paste-into-your-terminal-as-you-read-thing to show how you install Nim, write a small program, compile it and package it in a very short time.

To spice it up, for no specific reason at all, we are doing it all inside a Linux Container - a fast virtual environment to work in. It’s just a nice way to have a clean environment and to ensure that you as a reader see the same results as I do.

Nim crash course in LXC

Tue, 24 Oct 2017 00:00:00 +0000

Nim is an awesome programming language and this article is a whirlwind-copy-paste-into-your-terminal-as-you-read-thing to show how you install Nim, write a small program, compile it and package it in a very short time.

Benchmarking Spry vs Squeak

Fri, 26 Aug 2016 00:00:00 +0000

Spry is evolving quite nicely during my night hours. Focusing on performance is however still premature, but I do want to verify that I am not barking up the wrong tree, like … in the wrong forest even. So I make trivial benchmarks from time to time, just to see and learn.

Some background on the Spry implementation may be interesting. Spry is implemented in Nim as a direct AST interpreter, it’s not a JIT, in only about 2000 lines of code. It has a recursive classic “naive” design and uses a spaghetti stack of activation records, all allocated on the heap relying fully on Nim’s GC to do it’s work. It also relies on Nim’s method dynamic dispatch in the interpreter loop for dispatching on the different AST nodes. Blocks are true closures and control structures like timesRepeat: are implemented as primitives, normally not cheating. Suffice to say, there are LOTS of things we can do to make Spry run faster!

The philosophy of implementation is to keep Spry very small and “shallow” which means we rely as much as possible on the shoulders of others. In this case, primarily Nim and it’s superb features, performance and standard library.

Enough jibbering, let’s do some silly damn lies - ehrm, I mean silly tests!

Is Spry a Smalltalk?

Tue, 19 Jul 2016 00:00:00 +0000

I love Smalltalk and I have been in love with it since approximately 1994. I have used VisualWorks, VisualAge (IBM Smalltalk), Dolphin Smalltalk, GemStone, Squeak and Pharo quite a lot, and I was very active in the Squeak community for a long period.

But the last few years, finally, I have started to feel the “burn”… as in “Let’s burn our disk packs!” . And last year I started doing something about it - and the result is Spry . Spry is only at version 0.break-your-hd and several key parts are still missing, but its getting interesting already.

Now… is Spry a Smalltalk? And what would that even mean?

I think the reason I am writing this article is because I am feeling a slight frustration that not more people in the Smalltalk community find Spry interesting. :)

And sure, who am I to think Spry is anything remotely interesting… but I would have loved more interest. It may of course change when Spry starts being useful… or perhaps the lack of interest is because it’s not “a Smalltalk”?

Smalltalk family Link to heading

The Smalltalk family of languages has a fair bit of variation, for example Self is clearly in this family, although it doesn’t even have classes, but it maintains a similar “feel” and shares several Smalltalk “values”. There have been a lot of Smalltalks over the years, even at PARC they made different variants before releasing Smalltalk-80.

So… if we look at Spry, can it be considered a member of the Smalltalk family?

There is an ANSI standard of Smalltalk - but not many people care about it, except for some vendors perhaps. I should note however that Seaside apparently (I think) has brought around a certain focus on the ANSI standard since every Smalltalk implementation on earth wants to be able to run Seaside and Seaside tries to enforce relying on the ANSI standard (correct me if I am wrong).

Most Smalltalk implementations share a range of characteristics, and a lot of them also follow the ANSI standard, but they can still differ on pretty major points.

My personal take on things in Smalltalk that are pretty darn important and/or unique are:

Everything is an object including meta levels
A solid model for object oriented programming
The image model
100% live system
The browser based IDE with advanced cross referencing, workspaces and debuggers
The keyword syntax and message cascades
Message based execution model
Dynamic typing and polymorphism
Closures everywhere with lightweight syntax and non local return
Very capable Collections and a good standard library

Not all Smalltalks cover all 10. For example, there are several Smalltalks without the image model and without a browser based IDE. Self and Slate and other prototypical derivatives don’t have classes. Some Smalltalks have much less evolved class libraries for sure, and some are more shallow in the “turtle department”.

In Spry we are deviating on a range of these points, but we are also definitely matching some of them!

Fowltalk - a new Smalltalk

Sun, 19 Jun 2016 00:00:00 +0000

In my quest making Spry I also learned about other efforts in the Nim community to construct Smalltalk-like dynamic languages. The most ambitious one may be Fowltalk by “fowl” who typically hangs out in the #nim channel on Freenode. Fowltalk started out written in Nim but since fowl wanted to learn more C++ it’s now written in C++17.

At the moment he is rewriting the parser and code generator parts in the language itself , following a similar bootstrapping style as Ian Piumarta’s idst . For example, here is the method parsing keyword messages .

Spry Performance

Tue, 24 May 2016 00:00:00 +0000

When writing Spry I am so far mainly ignoring performance. The general execution of Spry code will be a regular interpreter (although stackless I hope) and not a JIT. But that doesn’t prevent us from playing around and learning something!

In this article I do some silly experiments around interpreter startup time and fooling around with 40 million element arrays. As usual, I am fully aware that the languages (Pharo Smalltalk, NodeJS, Python) I compare with a) have lots of other ways to do things b) may not have been used exactly as someone else would have done it. A truck load of salt required. Now… let’s go!

Spry vs Allen

Sat, 14 May 2016 00:00:00 +0000

Allen Wirfs-Brock wrote down a bullet list of what he thought actually made it possible for the Alan Kay team to create Smalltalk , and many other ground breaking things, at Xerox PARC in the 70s. Let’s take a look at his bullets one by one and see how it applies to Spry and my puny little effort around it :)

Spry Modules, part II

Tue, 03 May 2016 00:00:00 +0000

In the last article I outlined a simple model of modules and that is kinda implemented but needs a few fixes. The next step is how to find and combine modules and this is an area where I want to push the envelope a bit. Most popular package/module systems today are quite trivial in nature. Often it’s a command line tool that queries central catalog(s) and then proceeds by downloading code in the form of source files onto disk. Then the compiler or runtime environment finds and loads the code by simply looking for files on disk. There are several parts of this that are very primitive.

When I built SqueakMap waaay back I was already then tainted with the idea of shared object models and one of the primary ideas in SqueakMap was to make sure each local Smalltalk environment got a full live object model of the catalog which then could be queried, viewed and reasoned about inside the Smalltalk environment. Much more powerful than a bunch of JSON files on disk. This led to the approach of downloading the full catalog in a serialized form - and then loading it into Squeak .

With Spry I want us to create a simpler meta model - at least for starters - but with an even smarter infrastructure backing it…

Spry Modules

Sat, 16 Apr 2016 00:00:00 +0000

As discussed in the previous article I want Spry to have a trivially accessible persistence mechanism enabling something similar to the Smalltalk image model, but based on a database. The memory organisation in Spry is basically nested Maps. After dwelling a bit on the inevitable hard question about modules and namespaces I have decided on a design that I hope will turn out simple and reasonably powerful!

Smalltalk has a Dictionary holding all the globals forming “the roots” of the object memory. In Smalltalk this Dictionary is also itself a global variable accessible as Smalltalk, in other words Smalltalk == (Smalltalk at: #Smalltalk). The primary use of Smalltalk is to hold all classes by name, so they are all reachable as globals. Obviously Smalltalk can also hold any kind of object (not just classes) as a global.

Spry also has such a top level Dictionary, but in Spry we call a Dictionary a Map to be a little bit more aligned in terminology with other languages (and it’s shorter). This top level Map is the root Map and it is accessible via the word root. In Spry the root word is actually bound to a primitive function returning this Map, so in Spry we also have root == (root at: 'root).

Ok, so Spry has a Map of globals and one way of using Spry is simply by populating root with words bound to functions making these functions globally accessible, it’s how I have done it so far. Yeah, yeah, I know, but for smaller systems it probably works just fine!

But…

Spry image model

Sat, 09 Apr 2016 00:00:00 +0000

In developing Spry - renamed from Ni - I am getting closer to the Really Fun Stuff.

As a Smalltalker I dream “bigger” than just managing source code as text in files…

Smalltalk uses the “image model” in which the system is alive and running all the time, the full development environment is also live together with your application, and we are in fact modifying object structures when we develop Smalltalk programs. We can also snapshot that object memory onto disk and fire it up somewhere else. Several Lisp implementations have used a similar approach I think.

The image model has tons of really cool benefits, I don’t have time repeating all of them, but a modern implementation of the idea should take a few things into account that was not considered in the 1970s:

The “image” in Spry will be buildable from source
You should be able to use Spry without the image mechanism (you can already)
Spry code will have a readable text format and file structure
The image model does not have to be all or nothing, it can be partial
The image mechanism will be a module for the Spry VM, so you can skip it entirely

Some argue that the image model has downsides - like being an “ivory tower” incapable of interacting with the outside world. The Smalltalk environments have indeed historically suffered a bit in varying degree, but we can easily find ways around those issues while still reaping the awesomeness of a fully live programming environment, especially if we give the above items proper thought from the start.

With Spry I think I have a beginning to a novel approach… as well as taking the above into account.

Ni renamed to Spry!

Fri, 08 Apr 2016 00:00:00 +0000

When I started out implementing my own language in Nim I named it “Ni” without that much thought actually. It was a pun on “smaller than Nim” (obviously one letter shorter!) and of course with a reference to Monty Python .

But… really, the name “Ni” sucks. It’s hard to say in general and since it’s often mentioned together with Nim the confusion is obvious. And it also turned out to be less than optimal to google for.

Nim meets Arduino

Thu, 25 Feb 2016 00:00:00 +0000

I now work as the Team Lead at Evothings and our open source product is a Workbench for creating mobile HTML5 applications focused on IoT, by editing and running them live on the mobile device inside our spiced up Cordova based “Evothings Viewer”.

I am of course partial here - but the tool is really easy to use, doesn’t force you into any specific framework or editor, enables a very quick development cycle and has tons of examples, tutorials, docs and some special IoT focused libraries like for example around BLE (Bluetooth Low Energy). You can have your code running on your phone literally within 1-2 minutes and you don’t need to install XCode or the Android tools, you can even run it just fine from your trusty Linux laptop! Just go for it . Ok, enough of the sales talk…

Since we are specializing in the IoT space we have our office filled to the brink with toys… eh, I mean IoT devices of all kinds from all different vendors. Two IoT communication standards are particularly important in this space, and that’s BLE and MQTT. I have already written three blog posts around MQTT using Evothings. Now I am instead focusing on BLE and particularly the embedded device side of the story.

This led me to round up a bunch of devices at the office that are fairly technically capable and have BLE support. The one I selected was the LinkIt ONE development board from MediaTek & Seeed Studio . It’s an insanely feature packed little board (GSM/GPRS, GPS, Wifi, BLE, sound output, SD card) with decent computing power (ARM7 EJ-S, 16Mb flash, 4Mb RAM) while still remaining in the “medium” embedded space I would say, still ruling out plain Linux and regular tools. I consider the Raspberri Pi or C.H.I.P and similar machines to be in the “large” embedded space, they are real computers and you can basically use whatever you like to develop on those.

The medium and small devices can be programmed using for example Espruino or Micropython (two very interesting projects) but in many cases, for more demanding applications, C/C++ is still king simply because of size and performance advantages. And also the fact that hardware vendor SDKs are typically in C/C++. But could there be an alternative language out there?

A language that is just as fast and small that easily can use all these C/C++ SDKs?
A language with a syntax similar to Python made to be easy to write and read?
A language with soft realtime GC and a sane advanced type system with generics?
A language with a good standard library and friendlier than C++?
A language with compile time hygienic AST based macros written in the language itself?
A language offering an imperative style and not forcing OO if you don’t want to?

Yep! Read on to find out…

Elixir Booming

Tue, 27 Oct 2015 00:00:00 +0000

It seems like the “damp cloth of Java” that has been plastered all over the programming landscape the last 20 years is finally being lifted. I admit, I do dislike Java …immensely. And not only on technical grounds, but even more based on what I perceive as it’s community worshipping complexity for it’s own sake. Of course IMHO.

These days new and truly interesting languages are all over the place. Rust and Go are two examples with a lot of momentum, although I personally choose Nim over both.

And Smalltalk is still my “super productive dynamically typed” language of choice, but I just learned about a language that I really think is going places…

Adding objects to Ni!

Fri, 25 Sep 2015 00:00:00 +0000

So… Ni has almost reached the point where I can see objects appearing. The following describes the design I currently have in mind, read it and tell me what you think so I can scrap it and start over ;)

Ni design decisions!

Wed, 23 Sep 2015 00:00:00 +0000

So… my little Ni language got some attention since it was first on Hackernews , then TheRegister , all over Twitter and also Reddit .

But I think it managed to come relatively unscathed out of it, although it REALLY is pre-alpha-not-even-complete-eats-your-harddrive early and you know, I really have no idea if it ever will go the distance since it takes quite a bit of work to get a language to actually be used. But I am going to stick with it.

Anyway, I have been experimenting with “arg words” and “lookup scoping” while thinking about how to add objects, and a few other things. This article doesn’t introduce how I want to do objects, but the next one does (I split it in two). This article however covers a bunch of loose ends and my ideas on how to tackle them in Ni. And I will try to make this understandable even if you don’t know Ni. ;)

Guts of Ni

Tue, 22 Sep 2015 00:00:00 +0000

This article describes some core parts of the current implementation of the Ni (now known as Spry ) language. It’s not a tutorial, introduction or manual. It’s in fact kinda incoherent - but so is Ni :)

Who says Ni?

Wed, 16 Sep 2015 00:00:00 +0000

Ni is my own little language heavily influenced by Smalltalk but also other sources like Rebol, Forth, Lisp, Self and Nim. Ni is a bit strange, but it’s not academic and really meant to become something useful.

So put on your helmet and let me take you to the shrubbery…

Nim and super

Wed, 06 May 2015 00:00:00 +0000

As I described in the earlier posts Nim didn’t support “super calls” when using methods instead of statically bound procs and generics. My article caused a little bit of discussion around this on IRC and Andreas decided to implement the mechanism he already had planned - but had not fully decided a good name for.

The other day Nim 0.11.2 was released and it includes this mechanism. Let’s have a look how it works in my sample code…

Nim

Thu, 26 Mar 2015 00:00:00 +0000

Having been a die hard Smalltalker since 1994 I have finally found a new language and community that I am investing myself in. All the Ruby, Python, various JVM languages, C# and Mono etc - none has managed to capture my interest. Ruby and Python always felt like pale shadows of Smalltalk and I really don’t want to be tied to the Java eco system, no matter what. And so on and on, lots of languages looking interesting but not being able to withstand my deeper look. As a Smalltalker I probably have acquired a particular taste.

Since a few months I am however deeply into Nim. I have written a slew of articles about Nim, and at our company we have decided to bet hard on it. So far I have written a little utility called blimp in Nim, and I have helped creating Urhonimo - the Nim wrapper of the Urho3D game engine.

With a deeper understanding of Nim, although I am far from good at it, what is it that makes me recommend you to try it?

Nim visits GTUG Stockholm

Thu, 26 Mar 2015 00:00:00 +0000

Yesterday I had the pleasure of presenting the programming language Nim at the Stockholm GTUG . This evening we were around 50 people, I would guess mainly developers, listening to three presentations:

Rust , by Johan Burell, EVRY
Nim , by Göran Krampe, 3DICC
Go , by Marcus Olsson, Citerus

Now, that’s a pretty fitting trio of languages! :) This article is a little followup because I failed to mention so much stuff…

Nim seq

Wed, 03 Dec 2014 00:00:00 +0000

One of the most important aspects in a language is how powerful and easy it is to use its collection/container types. At least that is my feeling coming from Smalltalk where the Collection classes and their rather rich protocols are used extensively and also cover String and Array and much more. If you peek into the current leading open source Smalltalk - Pharo - you can see Collection allSubclasses size evaluate to 78. Of course, lots of those are special subclasses and not for general use, but fact remains that a strong language needs a strong library of good collections.

In Smalltalk I can for example run this:

#(1 2 3 4 5) select: [:x | x isOdd ] thenCollect: [:x | x * 3 ]

This is actually a single method call taking two closures, one to perform a “filtering”, and one to perform a “map”. This is not a standard message in “good old” Smaltalk-80, but it has eventually been added since the usage pattern is so common. To me personally a modern language needs similar power or I would go nuts. :)

Nim and OO, Part IV

Sun, 30 Nov 2014 00:00:00 +0000

The other day this mechanism entered the devel branch which means it will be official in the next release of Nim, which I suspect will be out before the end of 2014. It should be noted that devel is mainly undergoing bug fixing, so unless you are paranoid it’s pretty usable. Now… of course I had to try out super calls in my sample code…

Squeak to Nim, come in Nim...

Mon, 03 Nov 2014 00:00:00 +0000

In my exploration of Nim the turn has come to see how we can use Nim together with Squeak .

Squeak (and Pharo) has two basic mechanisms of interfacing with the C world:

Squeak VM plugins . That pdf is old, but still fairly accurate I guess.
Squeak FFI , Foreign Function Interface.

The VM plugins are basically a controlled way to introduce new “named” primitives in Smalltalk that can be invoked from Smalltalk. A plugin can be built either linked into the VM binary (statically) or as a dynamically loaded library (dll, so, dylib etc). When “all else fails” a plugin is the way to go, but they are a bit awkward to work with.

Then we have the FFI which is a generic way to dynamically call dynamically loaded libraries. In other words, no compilation step needed - just type the correct Smalltalk line and the library will load and the calls work. Now… sure, the FFI mechanism is a bit slower, since it needs to look at arguments and make the proper type conversions for the call. But the FFI is heavily used in the commercial Terf system, in fact, all the OpenGL calls are done through it. So its quite proven, and not that slow.

NOTE: There are in fact several FFIs today, the old one, the one called Alien and Pharo is brewing a new one called UFFI.

Let’s see if we can use the good old FFI with Nim.

Nim and OO, Part II

Fri, 31 Oct 2014 00:00:00 +0000

In the previous article when I explored OO mechanisms in Nim I felt I dropped the ball a bit in my Fruit example. This is a followup.

In that article we first implemented some Fruit “classes” mixing methods and procs. Then I presented a cleaned up version using methods only, and a teeny template in order to reuse a base method. This template was needed since Nim currently doesn’t have a “call-next-method-matching” for multimethods like Dylan or CLOS have. This is being discussed and I think all agree that there needs to be some mechanism so that you can call a “next lesser match” of all matching multimethods.

But I also wrote that the example can be written perfectly well using generics and procs only, thus ensuring static binding and maximum speed. But the “super call” problem also existed for procs, and the template hack was just a hack. After more experimentation I now think I found the proper Nim way to do this so let’s take a look…

Nim and OO, Part III

Fri, 31 Oct 2014 00:00:00 +0000

So previously in Nim and OO Part II we saw how we could solve the “super call” issue using only procs and generics in Nim . This means that all code is statically bound.

But if you have read all these article you know I also tried the more appropriate mechanism for OO - so called methods. In Nim a proc is a regular statically bound function, simple and fast. A method on the other hand uses dynamic multimethod dispatch on the runtime types of all object parameters. The easy way to do objects in Nim (with inheritance of behavior) is using methods - but of course, this means dynamic lookup that has a runtime cost, but quite small as we will see.

Time for benchmarking!

Nim and OO

Wed, 29 Oct 2014 00:00:00 +0000

Nim is presented as an imperative language. And yes, it has some of its roots in the Pascal line of languages, but it also has a set of powerful abstraction mechanisms making it very suitable for object oriented programming. And when I write “object oriented” I am referring to a broader flexible sense of OO in which objects can be formulated with attached behavior, polymorphism between different objects, some kind of reuse model of code (inheritance etc) and some type of dynamic dispatch.

Since I am a long time Smalltalker that is my main reference for “good OO” and not the … monstrous OO often seen in Java or C++. Its hard to explain the differences, but let me just say that OO in Smalltalk is elegant and natural, very much like in Ruby or Python - but ever so more streamlined. Smalltalk is a dynamically strongly typed reflective language with a heavily closure based style.

In this article I will try to make “sense” out of how to do OO in Nim.

I missed Nim

Mon, 20 Oct 2014 00:00:00 +0000

A year ago I wrote an article trying to round up new languages since year 2000 and what I think of them by just… glancing at them, or otherwise playing with them. I ended up sifting out the 4 most interesting in my not so humble opinion - Go , Rust , Dart and Julia . Now a year has passed and…

I discover that I missed Nim(Nimrod)!

Nim was born somewhere around 2006-ish and is clearly a very serious language to consider, but is going suspiciously under the radar. Having reviewed this language more closely (and still doing so) I can safely say that for me it actually easily tops this list.

I have already posted a few articles about Nim , but this one is meant as a followup to that article trying to make amends :).

NOTE: Technically Nim is still called “Nimrod” up to and including the 0.9.6-release that was done yesterday . But for the upcoming 0.10.0 and onward its Nim. Short and sweet.

ESUG in Annecy Day 4

Thu, 12 Sep 2013 00:00:00 +0000

It starts off with Cincom, Arden Thomas presenting their roadmap. He had a slide mentioning Jules Verne and I must ask him if he is aware of the influence from the books of Jules Verne - as Dan has explained, the ballon and the island in the classic Smalltalk logo comes from the Mysterious Island book .

ESUG in Annecy Day 3

Wed, 11 Sep 2013 00:00:00 +0000

Day three blurred a bit for me - lots of mingling and hacking intermixed with some nice presentations, but I missed quite a lot, I admit, like the presentation on new native UI stuff in VisualWorks and the tODE stuff from Dale Henrichs.

ESUG in Annecy Day 2

Tue, 10 Sep 2013 00:00:00 +0000

Another day in IAE Universite Savoie Mont-Blanc in Annecy.

Only writing about stuff I attended :)

ESUG in Annecy Day 1

Mon, 09 Sep 2013 00:00:00 +0000

Here we go! Time for a week of Smalltalking fun in IAE Universite Savoie Mont-Blanc in Annecy.

While ESUG this year is not super big, I think around 110 people or so, there were still quite a few arms raised when checking how many were here for the first time. The organisation seems impeccable, as always - thank you Stéphane Ducasse, Herve Verjus, Laurent Laffont and of course all volunteers!

Enough chit-chat, let’s get on with the talks…

New Languages After 2000

Sat, 07 Sep 2013 00:00:00 +0000

I am sitting in a gate on an airport waiting to go to ESUG so I felt I should finally get this article out the door. In a presentation earlier this year I asked what has happened in the programming language area since year 2000? Not much I felt and I couldn’t really name any interesting new language when thinking about it. But then I decided to look more closely and I can conclude I was at least partly wrong :)

So prepare for a long (too long) article digging through a whole bunch of languages trying to come up with the answer - Have any interesting programming languages appeared since year 2000?

(And at the end, how is the Smalltalk community doing?)