Posts tagged Racket

Thread names

:: Racket

Sometimes people want Racket threads to have useful names — for example to show in logger output. Here is one way to do it.

racket-mode

:: Racket, Emacs

Even though it’s been one of my most time-consuming projects, I’ve hardly blogged about racket-mode — an Emacs major mode for Racket. To change that, here’s a post giving an overview of how racket-mode works, as well as a look at how it might grow someday.

Racket Makefiles

:: Racket

A few years ago I wrote about makefiles for Racket. Some things have changed.

  1. The old makefile built and pushed documentation to a GitHub Pages branch of the repo. That’s no longer necessary: The Racket package catalog builds and hosts documentation.

  2. The Racket package catalog puts a yellow badge of shame on packages with missing dependencies (deps and build-deps in the package’s info.rkt). I want the makefile to check this.

  3. In .travis.yml files for Travis CI, I think the script section ought to simply invoke targets in the makefile — delegating details to the latter.

  4. Likewise some details needn’t even be in the makefile — they can move to the collection’s info.rkt. Example: The list of directories to clean.

  5. The old makefile had separate PACKAGENAME and COLLECTS variables; for single-collection packages they were the same value. I wanted to simplify this to just the package name and use the appropriate package variants of raco commands.

In that spirit, here’s an updated Makefile, which I recently started using in the rackjure, markdown, and frog projects.

Please scroll

:: Racket, Emacs

Recently I got more time to catch up on racket-mode. I improved two things that happen to fit one theme — an extraordinarily advanced UX concept I call, “scrolling down to the point of interest.”

At-expressions

:: Racket, racket-cookbook

If you’ve heard of Racket “at-expressions”, maybe you think they’re “that funny Scribble notation in which you write Racket documentation.”

In fact at-expressions are a general, alternative way to write s-expressions. They can be used in various handy ways.

Let’s look at using at-expressions for a few practical things like:

  • “string interpolation”
  • regular expressions
  • “here” strings

GitHub dropped Pygments

:: Racket, software

My first-ever open source contribution, a couple years ago, was to a project called Pygments. My motivation? GitHub was displaying Racket source code poorly. Pygments didn’t have a Racket lexer. GitHub was using a Scheme lexer for Racket code. The Scheme lexer was highlighting square brackets in red as an “error”. This was really distracting and ugly.

I contributed a new Racket lexer to Pygments, and waited for that to roll into a Pygments release and in turn be deployed on GitHub. Finally Racket code looked good! Later Dave Corbett substantially improved the Racket lexer beyond my small start.

A few days ago, I was confused to see that Racket code was displaying poorly again on GitHub. The square brackets were highlighted in red as errors — again??

Cartoon-me’s thought balloons: WAT, OMFG, FML, &c. Why are we going in circles?

Racket workflow

:: Racket

If you’re coming to Racket from another REPL language (such as another Lisp), this post might be real Captain Obvious material.

But if you’re coming to Racket from an edit/compile/debug language like C or C++, it might be unclear what a typical workflow is. You might have questions like:

  • How do I compile?
  • How do I debug?