Stream: bugs

Topic: InvalidMethodReceiver regression on some List functions

view this post on Zulip Matthieu Pizenberg (Dec 08 2025 at 21:26):

PR #8580 introduced a regression which seems to be very similar to the return error in #8589. This InvalidMethodReceiver error is triggered on both the concat function and the append function. Here is a minimal example, with both in the same main (though either one or the other is sufficient to trigger the crash).

app [main!] { pf: platform "./platform/main.roc" }

main! = || {
    _a = [].concat([1]).is_empty()
    _b = [1].append(1).is_empty()
}

Which when run, produces the following crash.

Roc crashed: Error evaluating from shared memory: InvalidMethodReceiver

view this post on Zulip Matthieu Pizenberg (Dec 08 2025 at 21:27):

I opened an issue for this regression: https://github.com/roc-lang/roc/issues/8593

Last updated: Dec 21 2025 at 12:15 UTC