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

["Dennis E. Hamilton" <dennis.hamilton@acm.org>]

I think there may be some conflicts between other draft content and the ODF 1.2 Part 1 cd01 rev06 language of 1.4.2.4 [D4.4]. 

(section 17.645 in the current draft is not helpful with simply the removal of typically.  Also, there is no definition of a default in the absence of a prefix, which is what I always thought the precursors to 17.645 were going on about, if anything.)

The current (2009-05-08) draft of OpenFormula is not so clear about this in section 1.3, although the Rationale suggesting a preference for an attribute value beginning with "=" and having no leading namespace prefix as the default for OpenFormula.

Section 5.1 of OpenFormula further recommends against using a prefix when there is an OpenFormula formula, making OpenFormula the default and using prefixes when it is not OpenFormula.  Also, the "=" is not optional, or if it is, forced recalculate should perhaps be signified by a "==" leader to avoid ambiguity. (That is, one "=" and no "=" would be the same, but "==" is never to be misunderstood.)

Alternatively, for historical reasons, one might want to leave omission of a prefix to mean "implementation-defined" and have a prefix be mandatory for any OpenFormula table:formula expression in ODF 1.2.  Whether at least one "=" is always required (in the OpenFormula case) is something that needs to be nailed down.

I suspect that introduction of a formula data type is not helpful, since there is nothing that can be said about it other than it being a string, *except* when it is identified as being an OpenFormula expression.  In the case of other namespaces and implementation-defined cases, that is something we cannot speak to, it seems to me.

I am not proposing anything in particular, just observing that there needs to be some discussion and tidying up in this area.

 - Dennis

-----Original Message-----
From: Eric Patterson [mailto:ericpa@exchange.microsoft.com] 
Sent: Wednesday, May 13, 2009 16:18
To: office-formula@lists.oasis-open.org
Subject: [office-formula] Table:formula attribute and the Formula data type

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" /