Clojurians Log v2
hyperfiddle 2025-03-18
Have not touched my electric repository for a while. No changes from my code but I am getting this when I try and start it.
Start of stack trace is:
Exception in thread "main" Syntax error macroexpanding at (hyperfiddle/electric/impl/lang3.clj:1:1).
Also later says it's related to contrib.
Caused by: java.io.FileNotFoundException: Could not locate contrib/assert__init.class, contrib/assert.clj or contrib/assert.cljc on classpath.
Did something change. I think I saw something about contrib changing.
Going to just try with a fresh starter.
Did get it working. Will leave messages here for search history.
Is this writeup still accurate? https://github.com/hyperfiddle/electric/blob/master/src/hyperfiddle/electric/impl/lang_3_walkthrough.md?plain=1
mostly yes, the analyzer passes are a bit out of date. Is this just out of curiosity? This documents compiler internals for our own needs and is subject to change
Now that you’re here, what is an Electric function in terms of Missionary?
internally it is a missionary flow. (e/pure electric-expr) returns the underlying missionary flow (incseq)
• calling an e/fn with zero args is like joining a missionary flow • any args are basically passed by dynamic scope
I think the docstring of e/input should be updated. It says “Returns the current state of current continuous flow cf“. In https://electric.hyperfiddle.net/tutorial/temperature2 it is being used with a discrete flow random-writer.
Or maybe I’m misunderstanding what it means for a flow to be continuous. I think a continuous flow is a flow which is always ready to transfer, so random-writer is not a continuous flow because after transferring 0 it is not ready to transfer again for one second.
the terms are defined loosely. Often we mean it is initialized, i.e. defined at all times. (m/ap (m/? (m/sleep 1000 :foo)) is not initialized, upon boot it has no value. (m/ap (m/amb :foo (m/? (m/sleep 1000 :foo)))) is well defined and you can call e/input on it because it has a value defined at all times
i.e. it is OK to join discrete flows iff they are initialized
There’s a new version of my code-coloring-for-Emacs thing. Highlights from the CHANGELOG:
• Don’t color Electric calls.
• Don’t color bound symbols when used in certain contexts:
◦ as an arg in an Electric call
◦ as the RHS of a binding pair.
• Provide an extension mechanism so that you can teach the mode about user-land binding macros.
• Support destructuring in let-bindings forms and fn-bindings forms.
See thread for details.
Looks nice! I wonder how hard it would be to do something similar with Calva
> Looks nice! Thanks! > I wonder how hard it would be to do something similar with Calva I don’t know — I’m not familiar with Calva.