Draft for review: ISO 8601 date work on IS 29500

[MURATA Makoto (FAMILY Given)]

Here is a rewrite.

sml_typeDesignatorAndContents = 
  (attribute t { string "b"}, element f { sml_CT_CellFormula }?,
                              element v { xsd:bool })
  | (attribute t { string "d"}, element f { sml_CT_CellFormula }?,
                                element v { xsd:date })
  | (attribute t { string "n"}?, element f { sml_CT_CellFormula }?,
                                 element v { xsd:long | xsd:float })
  | (attribute t { string "e"}, element f { sml_CT_CellFormula }?,
                                element v { s_ST_Xstring })
  | (attribute t { string "str"}, element f { sml_CT_CellFormula }?
                                  element v { s_ST_Xstring })
  | (attribute t { string "s"}, element v { xsd:short })
  | (attribute t { string "inlineStr"}, element is { sml_CT_Rst })

I still have some questions.

1) When @t="str", do we have to allow both <f> and <v>?
2) When @t="s", are permissible values of <v> xsd:short?
3) When @t="n", are permissible values of <v> xsd:long or xsd:float?  It
    appears that 9999999999999999 is silently converted to
                       9999999999999990.
4) When @t="b", can <v> contain true or false?  Or, can they
                          only contain 0 or 1?
Cheers,
Makoto