These are all great points, and I will update the blog post to reflect them in the morning.

I believe this approach can work while retaining the most apparently-idiomatic mapping. What do you guys think?

impl IRibbonExtensibility_Impl for Addin_Impl {

    unsafe fn GetCustomUI(&self, _ribbon_id: BSTR, out: *mut BSTR) -> HRESULT {

        log("GetCustomUI called()");

        std::mem::forget(_ribbon_id);

        if out.is_null() {

            return windows::Win32::Foundation::E_POINTER;
        }

        unsafe {

            std::ptr::write(out, BSTR::from(RIBBON_XML));
        }

        S_OK
    }

}

▲ garaetjjte 3 days ago | parent [-]

Looks fine to me, if you're avoiding wrappers like ManuallyDrop/MaybeUninit.

	▲	piker 2 days ago \| parent [-]
		Actually the `windows-rs` team weighed in: impl IRibbonExtensibility_Impl for Addin_Impl { `unsafe fn GetCustomUI( &self, _ribbon_id: windows::core::Ref<BSTR>, out: windows::core::OutRef<BSTR>, ) -> HRESULT { log("GetCustomUI called()"); if out.is_null() \|\| out.write(BSTR::from(RIBBON_XML)).is_err() { return E_POINTER; }; S_OK }` } https://github.com/microsoft/windows-rs/issues/3832 Thanks for pushing on the issue! I've updated the blog post for GetCustomUI.