njlr (Jan 13 2024 at 13:30): njlr (Jan 13 2024 at 13:30):Is optimizing away heap allocations something that Roc currently does?
Are there any docs / plans around this?
Brendan Hansknecht (Jan 13 2024 at 16:59):In what sense? Like what do you think is on the heap that could be optimized away? Any examples of this in other languages?
Brian Carroll (Jan 13 2024 at 18:40):We do reuse some allocations instead of making new ones. It's one of the things we do opportunistically if ref count is 1.
Sven van Caem (Jan 13 2024 at 18:41):Roc does a small-string optimization I believe, I suppose that saves a heap allocation?
Brian Carroll (Jan 13 2024 at 18:42):Another optimisation we've talked about is removing intermediate lists when you do a chain of operations like map, filter, map. But that's not implemented yet, and no immediate plans.
Kiryl Dziamura (Jan 13 2024 at 18:58):@Sven van Caem yep, you can learn more here: https://github.com/roc-lang/roc/blob/main/design/language/RocStr.md
njlr (Jan 13 2024 at 22:02):I talking about optimizations similar to "fusion" in GHC https://wiki.haskell.org/GHC_optimisations#Fusion
Intermediary lists are a good example.
Sven van Caem (Jan 13 2024 at 22:10):I believe that's what Brian meant! Either that or deforestation (I forget which is which), which is also planned
Notification Bot (Jan 13 2024 at 22:22):njlr has marked this topic as resolved.
Last updated: Jul 26 2025 at 12:14 UTC