Macro impl_vocabulary 

macro_rules! impl_vocabulary {
    (
        $ty:ty, $label:literal;
        $( $variant:ident => $canonical:literal $(, [ $($alias:literal),+ $(,)? ])? ; )+
    ) => { ... };
}

Generates code() and FromStr for a closed-vocabulary enum from one variant-to-spelling mapping.

The first spelling of each variant is its canonical code(); any further spellings are accepted aliases. Matching is on normalized forms, so separator and case variants need not be listed. The generated ACCEPTED associated constant is what the error message lists, so the parser and its advertisement are the same list.

impl_vocabulary! {
    ResetCompounding, "reset compounding";
    SpreadExclusive => "SpreadExclusive";
    Straight        => "Straight";
}