[office-formula] Table:formula attribute and the Formula data type

[Eric Patterson <ericpa@exchange.microsoft.com>]

Section 1.4.2.4 has the following to say about conforming spreadsheet documents:

1.4.2.4 Conforming OpenDocument Spreadsheet Document
 (D4.4)All table:formula attribute values shall be namespace prefixed and the namespace prefix shall correspond to the "urn:oasis:names:tc:opendocument:xmlns:openformula:1.0" namespace.
(D4.5)All table:formula attribute values shall conform to the syntax defined by OpenFormula


The above covers table:formula attributes and does not appear to apply to the formula data type.  This make the implementation of other structures that use the formula data type unclear.  For example, table:condition and style:condition reference the formula data type, but it is unclear whether formula strings for these should use OpenFormula syntax.  I propose that we be more clear about the intent here.  We should include something in 16.17.1.24 along the lines of "Formulas MAY conform to the syntax defined by OpenFormula.  Formula strings that conform to the syntax defined by OpenFormula shall be namespace prefixed..."




For reference, here is what the spec and schema say about this data type:

16.17.1.24 formula
A string containing a formula. Formulas don't have a predefined syntax, but should start with a namespace prefix that specifies the syntax used within the formula.


- <define name="formula">
- <!--  A formula should start with a namespace prefix,
  -->
- <!--  but has no restrictions
  -->
  <data type="string" /