Re: [office] OFFICE-3768 empty cell proposal for section 4.7 - next version

[Regina Henschel <regina.henschel@libreoffice.org>]

Regina Henschel schrieb am 03-May-20 um 22:21:
> Hi all,

considering the discussion, here the next proposal.

Still unclear how to handle <text:h> child element.

Excel can produce a cell with empty string by entering an apostrophe. 
While you are working on that spreadsheet, ISBLANK() returns FALSE for 
that cell. It is written out as markup <table:table-cell 
office:value-type="string" 
table:style-name="ce2"><text:p/></table:table-cell>. After reopening the 
file, ISBLANK() returns TRUE. So I consider this an error in Excel import.

Kind regards
Regina

New Proposal
============
4.7 empty cell
The technical term "empty cell" is used in this part of the 
specification in defining functions and expressions. The technical term 
"empty cell" stands for a cell, for which non of the following 
properties is true:
    The cell has a table:formula attribute.
    The cell has a non-empty <text:p> child element.
    The cell has an office:value-type attribute and the corresponding 
value attribute office:value, office:date-value, office:time-value, 
office:boolean-value, or office:string-value, respectively.
    The cell has an office:value-type="string" attribute and a <text:p> 
child element. In case of an empty child element <text:p/>, the cell 
contains an empty string.

It is implementation-dependent whether the markup 
<table:table-cell><text:p/></table:table-cell> is an "empty cell" or 
not. For interoperability producers should not write such markup, but 
add an office:value-type="string" attribute in case a cell with empty 
string is intended, or omit the empty child element <text:p/> in case an 
"empty cell" is intended.