Macro proc_macro_error::emit_error

macro_rules! emit_error {
    ($err:expr) => { ... };
    ($span:expr, $($tts:tt)*) => { ... };
}

Emit an error while not aborting the proc-macro right away.

The emitted errors will be converted to a TokenStream sequence of compile_error! invocations after the execution hits the end of the function marked with [proc_macro_error].

Syntax

See the guide.