Macro submit_step 

macro_rules! submit_step {
    ($name:ident, $kind:expr, $expr:expr, $handler:ident,) => { ... };
    ($name:ident, $kind:expr, $expr:expr, $handler:ident, regex = $is_regex:expr,) => { ... };
}

Convenience macro for submitting step registrations from proc macro expansion.