✔ Multiple bindgen's in the same package · wasmtime

Greetings, I would like to bind with the imports inside a module and then use these inside other modules.

world sensor {
    import wasi:i2c/i2c@0.2.0-draft;

    export hts;
}

world screen {
    import wasi:i2c/i2c@0.2.0-draft;
    import wasi:i2c/delay@0.2.0-draft;

    export lcd;
}

bindgen!({
    path: "../wit/deps/i2c",
    world: "wasi:i2c/imports",
    with: {
        "wasi:i2c/delay/delay": Delay,
        "wasi:i2c/i2c/i2c": I2c,
    }
});

bindgen!({
    path: "../wit",
    world: "sensor",
    with: {
        "wasi:i2c/i2c/i2c": I2c,
    }
});

error[E0364]: `I2c` is private, and cannot be re-exported
  --> src/sensor.rs:14:1
   |
14 | / bindgen!({
15 | |     path: "../wit",
16 | |     world: "sensor",
17 | |     with: {
18 | |         "wasi:i2c/i2c/i2c": I2c,
19 | |     }
20 | | });
   | |__^
   |
note: consider marking `I2c` as `pub` in the imported module
  --> src/sensor.rs:14:1
   |
14 | / bindgen!({
15 | |     path: "../wit",
16 | |     world: "sensor",
17 | |     with: {
18 | |         "wasi:i2c/i2c/i2c": I2c,
19 | |     }
20 | | });
   | |__^
   = note: this error originates in the macro `bindgen` (in Nightly builds, run with -Z macro-backtrace for more info)

I'm not sure why I get this error, nor how to resolve it. The I2c definition: pub struct I2c(pub I2cdev); and if I inline the macro the error becomes:

error[E0364]: `I2c` is private, and cannot be re-exported
   --> src/sensor.rs:221:21
    |
221 |             pub use super::super::super::I2c;
    |                     ^^^^^^^^^^^^^^^^^^^^^^^^
    |
note: consider marking `I2c` as `pub` in the imported module
   --> src/sensor.rs:221:21
    |
221 |             pub use super::super::super::I2c;
    |

Does anyone have any clues on what I could to debug further, or how to resolve this?

Jeff Schilling (Apr 09 2024 at 13:41):

how is I2c declared? and where? it should be pub struct I2c -(edit) I see the declaration now - still would try enhancing the with

you may also want to be more specific given that you're generating an interface named I2c - so change your with: ... to fully_qualified::path::to::I2c - the error messages will be better at any rate if you do that

Jeff Schilling (Apr 09 2024 at 13:43):

Christof Petig (Apr 09 2024 at 15:46):

My guess is that the world sensor should export i2c, given that you use with here to associate with your implementation.

Christof Petig (Apr 09 2024 at 15:49):

Oh, I guess that you should either use import exclusive or with for a given interface.

Christof Petig (Apr 09 2024 at 15:52):

Also I first guessed that this would be the host side, if you target the guest please use a more recent wit-bindgen (I don't see the export! macro and with no longer applies with newer versions)

Friedrich Vandenberghe (Apr 12 2024 at 12:17):

This fixed it! I honestly did not expect that such a simple change could fix it :happy:

Stream: wasmtime

Topic: ✔ Multiple bindgen's in the same package