Wouldn't it be nice if we could use proportional fonts to write code and still have things line up? Well, thanks to elastic tabstops, now we can. This editor implements that invention, and should serve as a reference for anyone who wants to implement it in other editors.
The reference implementation of the core elastic tabstops algorithm can be found in elasticTabstops.scala.
Since Elastic Notepad is written in Scala, you'll need to have Java installed to run it, specifically Java 14 or later.
The current version's settings default to using the fonts Merriweather and Inconsolata. If you don't have them installed, your system's default Serif and Monospaced fonts will be used instead. You can change Elastic Notepad's settings to use whatever fonts you like, but I recommend trying it with these fonts first. I've found this pairing to work well when you repeatedly switch between them (as you toggle elastic tabstops on and off).
On Windows at least, if you install Java for the sake of running this, it seems you'll need to restart your system before Java can use logical fonts properly. (So restart your system if you notice that toggling elastic mode off doesn't switch to a monospaced font and text doesn't appear lined up as a result.)
To run the jar file, use this:
java -jar elastic-notepad.jar
When developing, if necessary, switch to Java 14 or later using Coursier:
eval "$(cs java --jvm 14 --env)"
and then run it with:
mill app.run
and run the tests with:
mill app.test
If you are using IntelliJ IDEA, its project config files can be generated (and regenerated should the build definition change) with:
mill mill.scalalib.GenIdea/idea
You can build a new jar file with:
mill clean && mill app.assembly
Some systems do a poor job of rendering fonts in Java GUIs. On my Linux system
I've added the following line to $HOME/.profile to fix this:
export _JAVA_OPTIONS="$_JAVA_OPTIONS -Dawt.useSystemAAFontSettings=on"