Module headers 

Header field types and output traits shared by every protocol module.

• Header pairs a parsed authentication header with its raw name and value (RFC 5322 Section 2.2).
• HeaderWriter is implemented by every header this crate generates (DKIM-Signature, ARC-Seal and friends, DKIM2-Signature, Message-Instance, Authentication-Results, Received-SPF).
• Writer and Writable are the byte sink and source used for header output, canonicalization and hashing.
• HeaderFolder folds long header lines (RFC 5322 Section 2.2.3).

Structs

Header

An authentication header found in a message, as returned by AuthenticatedMessage accessors such as dkim_signatures() and errors().

HeaderFolder

A Writer adapter that folds header lines (RFC 5322 Section 2.2.3).

Traits

HeaderWriter

A header that can be written to a message.

Writable

A source of bytes that can be streamed into a Writer.

Writer

A byte sink: a buffer, a hash context or a HeaderFolder.