Mail::MimeVersion

     # File lib/mail/parsers/mime_version.rb, line 42
 42:     def _nt_version
 43:       start_index = index
 44:       if node_cache[:version].has_key?(index)
 45:         cached = node_cache[:version][index]
 46:         if cached
 47:           cached = SyntaxNode.new(input, index...(index + 1)) if cached == true
 48:           @index = cached.interval.end
 49:         end
 50:         return cached
 51:       end
 52: 
 53:       i0, s0 = index, []
 54:       r1 = _nt_CFWS
 55:       s0 << r1
 56:       if r1
 57:         s2, i2 = [], index
 58:         loop do
 59:           r3 = _nt_DIGIT
 60:           if r3
 61:             s2 << r3
 62:           else
 63:             break
 64:           end
 65:         end
 66:         if s2.empty?
 67:           @index = i2
 68:           r2 = nil
 69:         else
 70:           r2 = instantiate_node(SyntaxNode,input, i2...index, s2)
 71:         end
 72:         s0 << r2
 73:         if r2
 74:           r5 = _nt_comment
 75:           if r5
 76:             r4 = r5
 77:           else
 78:             r4 = instantiate_node(SyntaxNode,input, index...index)
 79:           end
 80:           s0 << r4
 81:           if r4
 82:             if has_terminal?(".", false, index)
 83:               r6 = instantiate_node(SyntaxNode,input, index...(index + 1))
 84:               @index += 1
 85:             else
 86:               terminal_parse_failure(".")
 87:               r6 = nil
 88:             end
 89:             s0 << r6
 90:             if r6
 91:               r8 = _nt_comment
 92:               if r8
 93:                 r7 = r8
 94:               else
 95:                 r7 = instantiate_node(SyntaxNode,input, index...index)
 96:               end
 97:               s0 << r7
 98:               if r7
 99:                 s9, i9 = [], index
100:                 loop do
101:                   r10 = _nt_DIGIT
102:                   if r10
103:                     s9 << r10
104:                   else
105:                     break
106:                   end
107:                 end
108:                 if s9.empty?
109:                   @index = i9
110:                   r9 = nil
111:                 else
112:                   r9 = instantiate_node(SyntaxNode,input, i9...index, s9)
113:                 end
114:                 s0 << r9
115:                 if r9
116:                   r11 = _nt_CFWS
117:                   s0 << r11
118:                 end
119:               end
120:             end
121:           end
122:         end
123:       end
124:       if s0.last
125:         r0 = instantiate_node(SyntaxNode,input, i0...index, s0)
126:         r0.extend(Version0)
127:         r0.extend(Version1)
128:       else
129:         @index = i0
130:         r0 = nil
131:       end
132: 
133:       node_cache[:version][start_index] = r0
134: 
135:       r0
136:     end

    # File lib/mail/parsers/mime_version.rb, line 8
 8:     def root
 9:       @root ||= :version
10:     end