Syntax

    pub const Syntax = union(enum) {
        /// A flag with no values.
        flag,
        /// An option which prefixes its (single) value.
        joined,
        /// An option which is followed by its value.
        separate,
        /// An option which is either joined to its (non-empty) value, or followed by its value.
        joined_or_separate,
        /// An option which is both joined to its (first) value, and followed by its (second) value.
        joined_and_separate,
        /// An option followed by its values, which are separated by commas.
        comma_joined,
        /// An option which consumes an optional joined argument and any other remaining arguments.
        remaining_args_joined,
        /// An option which is which takes multiple (separate) arguments.
        multi_arg: u8,
    }