Clojure Gazette 1.95

Om, Figwheel, Sente

Clojure Gazette

Issue 1.95September 28, 2014


Hi Clojurators,

I've been really busy this week. I've been researching and writing summaries and introductions to the Clojure/conj talks. The best way to make the most of your time at the Conj is to be prepared for the talks. There's still time to get prepared . I've also started interviewing the speakers. I'll publish those to the Pre-Conj list when they're ready.

Rock on!
Eric Normand

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Clojure Cup Apps

Clojure Cup is over. You can see the apps here, with descriptions and previews. Judging begins next week. Congratulations to all participants.

Google Summer of Code Results

A nice summary of the Google Summer of Code projects for Clojure. It seems like quite a lot was accomplished in a short time.

Common mistakes to avoid when creating an Om component

I've been doing a lot of Om development recently and these were helpful. I've definitely wasted time on some of these mistakes.

Draggable wrapper component with Om and core.async

I'm glad to see that people are starting to share their Om components.

Nil works well for Clojure error handling

I think this is an important point to make: nil is not perfect, but it does work well because of the semantics for using nil in Clojure. In Java, not much can be done with null, but in Clojure, it is more useful. This post does a good job of explaining that.


Another library I've been using and enjoying recently. This is a realtime web client/server communication library. It will use websockets or fall through to other technologies, all with the same interface. Very nice when it all starts clicking together.


This library makes developing web clients in ClojureScript into a much more enjoyable experience. It will automatically compile your ClojureScript source each time it changes and *notify the client of the change so it can reload it. * It means you can type code in one window, save it, and watch the effect almost immediately in the browser. There's a nice intro with a video .

Figwheel Keep Om Turning

A nice explanation of how to set up Figwheel for use with Om. There are some gotchas that you should be aware of, and this post walks you through avoiding them.