pub fn new(from: Option<EmailAddress>, to: Vec<EmailAddress>) -> EmailResult<Envelope> {
        if to.is_empty() {
            return Err(Error::MissingTo);
        }
        Ok(Envelope {
            forward_path: to,
            reverse_path: from,
        })
    }
/// Creates a new envelope, which may fail if `to` is empty.
Creates a new envelope, which may fail if `to` is empty.
Creates a new envelope which may fail if ` to ` is empty .
pub fn new(from: Option<EmailAddress>, to: Vec<EmailAddress>) -> EmailResult<Envelope> {
        if to.is_empty() {
            return Err(Error::MissingTo);
        }
        Ok(Envelope {
            forward_path: to,
            reverse_path: from,
        })
    }
pub fn new ( from : Option < EmailAddress > , to : Vec < EmailAddress > ) -> EmailResult < Envelope > { if to . is_empty ( ) { return Err ( Error :: MissingTo ) ; } Ok ( Envelope { forward_path : to , reverse_path : from , } ) }
Creates a new envelope, which may fail if `to` is empty.
Creates a new envelope which may fail if ` to ` is empty .
from
Option<EmailAddress>
to
Vec<EmailAddress>
from
Option<EmailAddress>
to
Vec<EmailAddress>