# File lib/mail/parsers/content_type.rb, line 311 def _nt_sub_type start_index = index if node_cache[:sub_type].has_key?(index) cached = node_cache[:sub_type][index] @index = cached.interval.end if cached return cached end i0 = index r1 = _nt_extension_token if r1 r0 = r1 else r2 = _nt_iana_token if r2 r0 = r2 else @index = i0 r0 = nil end end node_cache[:sub_type][start_index] = r0 r0 end