ClassFromString returns the class from the string s.

Classify classifies the Type t, it returns its Class.

TypeFromString returns the type from the string s.

Typify classifies a message, it returns the Type.

All is a meta class encompassing all the classes.

Delegation is a msg with a pointer to another nameserver: NOERROR in header, NS in auth, optionally fluff in additional (not checked).

Denial is a class for denying existence (NXDOMAIN, or a nodata: type does not exist).

Error is a class for errors, right now defined as not Success and not Denial.

Meta indicates a meta message, NOTIFY, or a transfer: qType is IXFR or AXFR.

NameError is a NXDOMAIN in header, SOA in auth.

NoData indicates name found, but not the type: NOERROR in header, SOA in auth.

NoError indicates a positive reply.

OtherError indicates any other error: don't cache these.

Success is a class for a successful response.

Update is an dynamic update message.

Class holds sets of Types.

Type is the type of the message.