Macro tx_channels 

macro_rules! tx_channels {
    (
        $vis:vis struct $channels:ident : $id:ident {
            $($body:tt)*
        }
    ) => { ... };
    ({ $($rest:tt)* }) => { ... };
    ($($rest:tt)+) => { ... };
}

Declares the transmit channels of a CuBridge implementation.

Examples

tx_channels! {
    esc0 => EscCommand,
    [publish_empty] esc1 => EscCommand = "motor/esc1",
}

tx_channels! {
    pub(crate) struct MyTxChannels : MyTxId {
        state => StateMsg,
    }
}

Channels declared through the macro gain #[repr(usize)] identifiers and an inherent as_index() helper that returns the zero-based ordinal (matching declaration order), which is convenient when indexing fixed arrays.

By default, Tx channels skip bridge send calls when their upstream CuMsg has no payload. Prefix a Tx declaration with [publish_empty] to keep metadata-only sends enabled for backends that support them.