[Vanilla] Error when tracing/instrumenting core.match macro that references local bindings in :or pattern

[formsandlines]

When I try to trace or instrument code that uses the core.match/match macro with a local let-binding inside of an :or pattern, like this:

(ns … (:require [clojure.core.match :refer [match]]))

#rtrace (let [foo "coffee"]
          (match ["coffee"]
            [(:or foo "bar")] :yes
            :else :no))

I get the following error: “No method in multimethod 'to-source' for dispatch value: null”.

It works just fine when I use the binding outside of :or, as in [foo].

I know this is a very specific issue. Any idea what could be causing it?

[jpmonettas]

Thanks for reporting the issue @formsandlines.

The issue is related to that macro not working even with Clojure macroexpand :

(macroexpand-1 '(match ["coffee"] [(:or foo "bar")] :yes :else :no))

you get that exact same error Syntax error macroexpanding match at (*cider-repl my-projects/hansel:localhost:34779(clj)*:14:6). No method in multimethod 'to-source' for dispatch value: null

So I'll have to trace down that issue first, and maybe it can be hacked somehow 🤔

Or maybe we should report the issue to the core match project, but I'm not sure I would consider that a core.match issue.

[jpmonettas]

This works fine in ClojureStorm which is the recommended way.