Could not find `class` in `com`

[Rike-cz]

I really do not know, why is com::interfaces! macro accepted and following macro com::class! is unknown. (Rust v. 1.56.1)

   Compiling proc-macro2 v1.0.32
   Compiling unicode-xid v0.2.2
   Compiling syn v1.0.81
   Compiling quote v1.0.10
   Compiling com_macros_support v0.6.0
   Compiling com_macros v0.6.0
   Compiling com v0.6.0
   Compiling vfp v0.1.0 (C:\apps\rust\vfp)
error[E0433]: failed to resolve: could not find `class` in `com`
  --> src\lib.rs:23:6
   |
23 | com::class! {
   |      ^^^^^ could not find `class` in `com`

error: could not compile `vfp` due to previous error; 1 warning emitted

Whole lib.rs file taken from docs:

use com::sys::{HRESULT, IID, NOERROR};
use core::ffi::c_void;

com::interfaces! {
    #[uuid("00000000-0000-0000-C000-000000000046")]
    pub unsafe interface IUnknown {
        fn QueryInterface(
            &self,
            riid: *const IID,
            ppv: *mut *mut c_void
        ) -> HRESULT;
        fn AddRef(&self) -> u32;
        fn Release(&self) -> u32;
    }

    #[uuid("EFF8970E-C50F-45E0-9284-291CE5A6F771")]
    pub unsafe interface IAnimal: IUnknown {
        fn Eat(&self) -> HRESULT;
    }
}

com::class! {
    pub class BritishShortHairCat: ICat(IAnimal), IDomesticAnimal(IAnimal) {
        num_owners: u32,
    }

    impl IDomesticAnimal for BritishShortHairCat {
        fn Train(&self) -> HRESULT {
            println!("Training...");
            NOERROR
        }
    }

    impl ICat for BritishShortHairCat {
        fn IgnoreHumans(&self) -> HRESULT {
            println!("Ignoring Humans...");
            NOERROR
        }
    }

    impl IAnimal for BritishShortHairCat {
        fn Eat(&self) -> HRESULT {
            println!("Eating...");
            NOERROR
        }
    }
}

[sivadeilra]

You need to enable the production feature.

I run into this a lot, myself. I might work up a PR that at least suggests a fix, when that feature is not enabled.

[sivadeilra]

I've opened #232 to provide a better error message in this situation.

[Rike-cz]

@sivadeilra Thanks a lot for help.
Maybe some standalone example with comments would be good for newbies. I stucked in "entry point DllRegisterServer missing" when registering via regsvr32 and really do not know what's wrong. Also inproc_dll_module macro is deep magic :-)