WasmEdge supports passing complex struct data type already?

[KeeganJin]

Hi all,
Last time I checked the landing page, I found WasmEdge supported Scalar types, String, Vec as Parameter and Scalar types, String, Vec, Tuple, and Result as return values.

But I surprisingly found that it already supported returning complex struct data types (nested) after checking out the wasmedge-bindgen examples. Thanks for the great work.

Is passing complex struct data types(nested) as parameters also supported? Thanks :>

[hydai]

Hi @apepkuss
Can you help answer this?

[apepkuss]

@KeeganJin The answer is Yes. Suppose that you have a complex type named Point, and wanna pass an instance of this type to a host function.

struct Point {
    x: f32,
    y: f32,
}

What you need to do is to implement serde::{Deserialize, Serialize} traits:

#[derive(Serialize, Deserialize, Debug)]
struct Point {
    x: f32,
    y: f32,
}

(just as shown in this code)

Each time you wanna pass a value of Point type to a target host function, just serialize the value to a string, and then pass the string to the function (just as shown in this code. In the host function, you just deserialize the string to the original value of Point type first, then you can use it in the host function.

Hope the explanation above can help you! Thanks a lot!

[dmd17]

@apepkuss when will passing complex data types be supported in C/C++ SDK ?

[hydai]

Hi @dmd17
Currently, we have yet to make a plan for supporting the complex types in C/C++ SDK. The previous bindgen is based on wasm-bindgen. However, the generated output is unstable and may break when bumping the version. Unless there is a contributor who would like to take over maintaining the synchronization, this is no longer on our milestones.

[dmd17]

Thank you. I'll have a look. The previous bindgen is which? this one https://github.com/second-state/wasm-bindgen ?

related to this question, how can we pass a binary blob from native in C to wasm?

[dannypsnl]

I think you can use WasmEdge_MemoryInstanceGetPointer or WasmEdge_MemoryInstanceSetData.

[apepkuss]

@hydai Could you please help answer the question about C/C++ SDK from @dmd17? Thanks a lot!