Enum iron::headers::Vary  
            [-] [+]
        [src]
pub enum Vary {
    Any,
    Items(Vec<UniCase<String>>),
}Vary header, defined in RFC7231
The "Vary" header field in a response describes what parts of a request message, aside from the method, Host header field, and request target, might influence the origin server's process for selecting and representing this response. The value consists of either a single asterisk ("*") or a list of header field names (case-insensitive).
ABNF
Vary = "*" / 1#field-name
Example values
accept-encoding, accept-language
Variants
Any | Any value is a match  | 
Items | Only the listed items are a match  |