On Microsoft "Visual" products

The logo from Visio version 1.0

This post is intended as support material for another post I am writing about visual software design tools.

One day back in the early nineties, when people were using Windows 3.0 and programming with the Microsoft C/C++ Compiler, a colleague showed me a software design that for the first time he had done not on whiteboard, nor on paper, but on a computer screen, using a new drawing tool called Visio. 

Screenshots of Visio 1.0 running under Windows 3.1. Click to enlarge.

He showed me interconnected components laid out on a canvas, and as he moved one of the components, the drawing tool re-routed the lines to maintain the connections to other components. This meant that Visio was not just a pixel drawing utility like Microsoft Paint; it had some understanding of the structure of the information that was being displayed. 

On Visual Programming Languages

Logos of various visual programming languages

This post is intended as support material for another post I am writing about visual software design tools.

The idea of creating software using visual tools has existed ever since the first aspiring programmer was bitterly disillusioned by discovering that programming consists almost exclusively of writing and manipulating lots and lots of little text files containing nothing but boring and cryptic text.

On UML (do not even get me started)

The UML logo, by Object Management Group®, Inc. from uml.org; Public Domain.

This post is intended as support material for another post I am writing about visual software design tools.

UML (see Wikipedia) was intended to be a standard notation for expressing software designs, and to replace the multitude of ad-hoc notations that software architects have been using on various mediums such as whiteboard, paper, and general-purpose box-and-arrow diagram-drawing software. The idea was that by following a standard notation which prescribes a specific way of expressing each concept, every design would be readily and unambiguously understood by everyone.

It has miserably failed.

Common mistakes Dutchies make in the use of English

City Skyline Across Body Of Water In The Evening In Rotterdam, The Netherlands by Scopio from NounProject.com

Object-adjective instead of adjective-object.

"I will learn you how to skate." ("Learn" instead of "Teach".)

"When you want, we also have it in white." ("When" instead of "If".)

"Let's meet at sex." ("Sex" instead of "Six".)

"Dear colleagues, hereby the schedule." ("Hereby" instead of "Here is" or "Hereby I give you".)

"I am a cineville" ("cineville" instead of "cinefille") -- there is even a .nl domain misspelled this way.

"We have lot's of bicycle's" (Genitive instead of plural suffix.)

"Meet you at the busstop" (Concatenating words that are not normally concatenated in English.)

Dutch pronunciation rules cause some really weird phenomena, for example when you call Vodafone, the operator informs you that you have reached "Fodavone".

A Programming Language

"Coding Software Running On A Computer Monitor" by Scopio from NounProject.com

Abstract

My thoughts and notes on how I would like a new programming language to look like.

The main goals of the language are:

• Simple and elegant. (So that it is suitable for the academia.)
• Expressive. (So that it is suitable for experienced programmers.)
• Consistent. (So as to be attractive to developer teams.)
• Fast. (So that it is suitable for high performance computing.)
• Lean. (So that it is suitable for resource-constrained computing.)

This is work-in-progress; It is bound to be heavily amended as time passes, especially if I try some new language, like Kotlin or Rust.

Summary of language characteristics

And now, for something completely different... in Java

Summary

This post presents a coding construct for Java which reduces the total number of lines of code necessary to declare and initialize fields whose values are copied or computed from constructor parameters.

The problem

Let us suppose we want to write a class which exposes a `greet()` method that prints "Hello, <name>!" where <name> has been passed as a constructor parameter. Here is a trivial implementation:

Why the majority is always wrong | Paul Rulkens | TEDxMaastricht

I knew I was definitely going to watch this one, from just the title. It turns out that he comes across a bit annoying due to attitude; nonetheless, the talk is definitely worth watching.

Bret Victor - Inventing on Principle

Interestingly enough, in his code snippets he is using JavaScript, whereas one of my personal guiding principles is thou shalt not suffer an error to go undetected, which means that no scripting language should be used for anything at all, anywhere, ever. But, I digress. Excellent presentation.

Bathyscaphe

The Bathyscaphe logo, a line drawing of bathyscaphe Trieste

by Mike Nakis, based on art found at bertrandpiccard.com

Abstract

This article introduces Bathyscaphe, an open-source java library that you can use to assert that your objects are immutable and/or thread-safe.

The problem

Programmers all over the world are embracing immutability more and more; however, mutation is still a thing, and in all likelihood will continue being a thing for as long as there will be programmers. In a world where both mutable and immutable objects exist side by side, there is often a need to ascertain that an object is of the immutable variety before proceeding to use it for certain purposes. For example, when an object is used as a key in a hash map, it better be immutable, or else the hash code of the key may change, causing the map to severely malfunction.

Furthermore, when an object is not immutable, there is often the need to ascertain that it is at least thread-safe before sharing it between threads, otherwise there will be race conditions, with catastrophic results.

Note that when any of the above goes wrong, it tends to be a bug which is very difficult to troubleshoot.

Fixing broken module names in IntellijIdea

Quite often, when I rename a maven module, IntellijIdea gets confused and keeps showing the old module name in the project view.

• Re-importing maven projects does not help.
• Clearing the IntellijIdea caches and restarting does not help.
• Even deleting the .idea directory does not help.

I discovered that this is happening because: 

• IntellijIdea keeps information about a project outside of the .idea directory
• IntellijIdea fails to delete that information when you invalidate caches and restart.

The solution I have found to this problem is:

1. Exit IntellijIdea.
2. Go to the application data directory of IntellijIdea (on my Windows machine, this currently is %USERPROFILE%\AppData\Local\JetBrains\IdeaIC2022.1)
3. Delete the `external_build_system` subdirectory
4. Start IntellijIdea.
5. Re-import all maven projects.

Update:

Shortly after I discovered this, a new release of IntelliJ IDEA came out, (IdeaIC2021.3) and there appears to be no "external_build_system" subdirectory in its directory. Miraculously, it makes use of the "external_build_system" subdirectory of the IdeaIC2021.1 directory!

Also, with this new version, when I apply the above steps, IntellijIdea for some reason starts to believe that I have chosen to "ignore" all of my pom.xml files.  So, I have to open up maven settings, go to "Ignored Files", and uncheck every single one of my pom.xml files.