ambiguity in BNF: no non-numeric TLDs?

Can we assume that TLDs will be non-numeric? 

It looks to me that the BNF is ambiguous between
hostname and IPv4 addresses because the
BNF for hostname doesn't rule out
  nnn.nnn.nnn.nnn

Larry

Received on Wednesday, 12 November 2003 14:26:12 UTC