Daniel Macovei (Mar 16 2023 at 19:09): Daniel Macovei (Mar 16 2023 at 19:09):https://bytecodealliance.zulipchat.com/#narrow/stream/206238-general/topic/cargo.20component.20param.20vs.20result/near/342360176
I asked a question over in general pertaining to cargo component, and realized later that this is probably the place for it.
Daniel Macovei (Mar 16 2023 at 19:11):Essentially wondering if it makes sense to add a From trait to convert between TypeParam and TypeResult types in bindings that are generated, so that return types of one wit import can be passed to another
Daniel Macovei (Mar 16 2023 at 19:12):Cows were brought up as another solution
Lann Martin (Mar 16 2023 at 19:17):^ In particular, unifying *Param and *Result by using Cows for heap-allocated fields
Alex Crichton (Mar 16 2023 at 20:19):Another option here would be https://github.com/bytecodealliance/wit-bindgen/issues/535, which I think would be reasonable to turn on by default, which is to always generate APIs with owned types and only optionally generate the *Param and *Result structures
Alex Crichton (Mar 16 2023 at 20:20):I'm not sure that anyone really wants the *Param and *Result stuff anyway, it's just how I implemented it originally because I assumed we'd want it for performance but in the end it's so confusing I don't think it's worth it
Daniel Macovei (Mar 17 2023 at 14:18):ah yeah, looks like that would take care of it too
bachrc (Mar 18 2023 at 16:31):I permit myself to link the topic where I struggle with the same topic https://bytecodealliance.zulipchat.com/#narrow/stream/327223-wit-bindgen/topic/.5Brust.5D.20param.20and.20result.20structs
bachrc (Mar 18 2023 at 16:43):Actually, it is pretty hard to just give a Vec as a parameter. The Param works for inlining a parameter, but when you need to give a list of objects, and give it as a parameter... this is a lifetimes hell
Last updated: Jan 10 2026 at 20:04 UTC