Stream: beginners

Topic: ✔ Mastodon post

Hannes (Nov 15 2023 at 23:39):

Hi, can someone who's more knowledgeable about Roc's internals contribute to this thread on Mastodon?

Luke Boswell (Nov 16 2023 at 00:01):

Well I think the new site answers some of this in the Fast, Friendly and Functional pages... but it's not quite released yet. It's WIP and should be done very soon. https://www.roc-lang.org/wip/

Luke Boswell (Nov 16 2023 at 00:03):

I wouldn't be confident enough to give an answer directly. I assume this is related to opportunistic in place mutations.

Richard Feldman (Nov 16 2023 at 00:14):

@Hannes I'd say link to https://vimeo.com/653510682 at like the 32:30 mark (that talk goes into the technical details of how basically everything in Roc is implemented except I think dictionaries and sets maybe?)

Richard Feldman (Nov 16 2023 at 00:15):

and maybe https://www.microsoft.com/en-us/research/publication/perceus-garbage-free-reference-counting-with-reuse/

Richard Feldman (Nov 16 2023 at 00:17):

but yeah short answer is:

• Roc's List basically looks like a Rust Vec or a C++ std::vector except with a reference count added to the heap allocation (and also seamless slice support, but that's not really relevant to the question)
• if the reference count is 1, we update it in place
• thanks to Morphic, sometimes we don't even need to check the reference count - I gave more details on this in https://youtu.be/vzfy4EKwG_Y?si=_u2ZOvx7pzOv2t-4&t=1444
  

Richard Feldman (Nov 16 2023 at 00:17):

so yeah it's in place, not cloning, but if the reference count were more than 1, then the whole thing would be cloned

Hannes (Nov 16 2023 at 03:32):

Thanks Richard, I've replied in the thread with that info :+1:

Notification Bot (Nov 16 2023 at 03:32):

Hannes has marked this topic as resolved.

Notification Bot (Nov 17 2023 at 18:46):

Ryan Bates has marked this topic as unresolved.

Notification Bot (Nov 17 2023 at 18:51):

Ryan Bates has marked this topic as resolved.

Last updated: Jul 26 2025 at 12:14 UTC