Yadid

Yadid is a Visual Studio Code extension for the 8th programming langauge. Yadid ("friend" in Hebrew) gets its name from the fact that 8th's creator - Ron Aaron - lives in Israel, and I like to think of this extension as a friendly contribution to the community.

Note: Since 8th libraries do not use the .8th file extension, I also highly recommend installing the Modelines extension, which will let you identify 8th your source code to VSCode from within the source files themselves (like Vim and Emacs).

Features

Forth - and its derivatives - are actually quite frustrating to make an effective extension and syntax highlighter for. This is because they have little-to-no syntax and are very context dependent. For this reason, Yadid's primary goals are to provide:

• Context-aware syntax highlighting
• Quick running of the current file as an 8th script
• Building the project in the current workspace
• Opening build GUI for current workspace
• Open new editor window to core/user libraries folder
• Code snippets

Context-Aware Syntax Highlighting

Yadid's syntax highlighting has no intention - nor will it ever - of highlighting every known word in the dictionary. I personally believe this is not only difficult to maintain, but an eye sore and not effective. It would be like a C syntax highlighter only calling attention to the libc functions and nothing else. Of what use is that to anyone? Instead, Yadid highlights words that fit one of the following criteria:

• Defining words (e.g. :, var, ns:, constant)
• State-changing words (e.g. (, ;)
• Immediate and parsing words (e.g. needs, ', p:, with:)
• Control-flow words (e.g. if, then, while, again)
• Exiting words (e.g. null;, ;if)

In addition, because Yadid is picky about this, it can go further and only highlight those words in the state(s) they are legally allowed to be used in! This is where Yadid shines. For example, consider the following animation of code being edited and notice how the highlighting changes based on the state:

Notice how when defining the word run-test that : run-tests is no longer highlighted until after the definition of run-test is ended and back in interpret mode. And, when replacing the anonymous word ( test drop ) with ' run-test, the closing ) becomes unhighlighted once the opening ( is deleted.

There are many of these situations for which I hope Yadid will be very helpful. I've found this especially true with respect to literal arrays and maps. For example, literal characters are not allowed in literal arrays (this has bit me multiple times) and so won't be highlighted there.

Running 8th Scripts

The currently open file can be run as an 8th script with the "Run File" command (F6) or the "Run File with Arguments" (Ctrl-F6).

Project Building

If open in an Workspace and there is a 8th build project setup in the folder, then the "Build Project" (Ctrl-Shift-B) command can be used to build it. Likewise, the "Launch Build GUI" command can be used to start the 8th build GUI to create a project, change its configuration, or build it.

Opening Libraries

Quite often you want to either look at a library for reference or need to make quick edits in one of your own libraries. The "Open Libaries Folder" and "Open Core Libraries Folder" command palette actions will launch a new VSCode window and immediately open the libraries folder you selected. The core libraries folder is always considered to be relative to the 8th executable, which the user libraries folder is relative to the EIGHTHLIB environment variable.

Requirements

This extension assumes you have 8th installed, that it exists in your PATH somewhere, and (to build projects) that the build binary is up one directory from the 8th executable as it would be in a standard installation.

Known Issues and Quirks

In order to guarantee that what's highlighted is valid 8th code, there are a couple areas where what isn't highlighted is valid 8th, but doesn't show that way. Put another way, there may be a few cases that present false negatives, but there should be no false positives.

Literal arrays and map items not padding the , delimiter:

[true,false]  \ valid 8th, but won't highlight correctly

Defining words on the different lines:

:
foo  \ valid 8th, but won't highlight correctly
;

Regular expressions are distinguished from n:/ by assuming that any / paired with another / with no whitespace between them is a regular expression. Of course, this means that a regular expression with whitespace in it won't highlight correctly.

The effort required to correct these (very minor) issues would be untenable, though. I can't see myself even attempting to do so.

Future Plans

There are a couple features that I still plan on adding:

• Highlight words that are in the wrong state as errors
• Run script in an external shell as opposed to the embedded terminal
• Somehow add user-defined immediate words (i:) as to-be-highlighted

Bugs and Feature Requests

If you find something that you think is wrong or have a feature request, feel free to open up an issue on GitHub. Also, if you find this extension helpful and want to give a shout-out, a great place to do so would be on the 8th forums!