Simon Willison’s Weblog

Tuesday, 26th April 2022

HTML event handler attributes: down the rabbit hole (via) onclick=“myfunction(event)” is an idiom for passing the click event to a function—but how does it work? It turns out the answer is buried deep in the HTML spec—the browser wraps that string of code in a function(event) { ... that string ... } function and makes the event available to its local scope that way. # 8:35 pm

Mac OS 8 emulated in WebAssembly (via) Absolutely incredible project by Mihai Parparita. This is a full, working copy of Mac OS 8 (from 1997) running in your browser via WebAssembly—and it’s fully loaded with games and applications too. I played with Photoshop 3.0 and Civilization and there’s so much more on there to explore too—I finally get to try out HyperCard! # 7:16 pm

Learn Go with tests. I really like this approach to learning a new language: start by learning to write tests (which gets you through hello world, environment setup and test running right from the beginning) and use them to explore the language. I also really like how modern Go development no longer depends on the GOPATH, which I always found really confusing. # 7:12 pm

jq language description (via) I love jq but I’ve always found it difficult to remember how to use it, and the manual hasn’t helped me as much as I would hope. It turns out the jq wiki on GitHub offers an alternative, more detailed description of the language which fits the way my brain works a lot better. # 7:04 pm

A tiny CI system (via) Christian Ştefănescu shares a recipe for building a tiny self-hosted CI system using Git and Redis. A post-receive hook runs when a commit is pushed to the repo and uses redis-cli to push jobs to a list. Then a separate bash script runs a loop with a blocking “redis-cli blpop jobs” operation which waits for new jobs and then executes the CI job as a shell script. # 3:39 pm

2022 » April