20111119
========


Incomplete dates
----------------

Lino now allows to store incomplete dates
like "1978-00-00" or "1978-06-00".
New classes
:class:`lino.utils.IncompleteDate`,
:class:`lino.fields.IncompleteDateField`,
:class:`lino.utils.bcss.IncompleteDateField`
:class:`lino.ui.extjs.ext_elems.IncompleteDateFieldElement`
and
`Lino.IncompleteDateField` in :xfile:`linolib.js`.

:class:`lino.modlib.contacts.models.Born` uses this for a 
Person's `birth_date` field.


Background:
There are quite some people who don't know their exact birth date.
That's no reason to not get registered in Belgium!
:term:`BCSS` accepts birth dates.

Note that we limit to the cases of incompleteness managed by 
the :term:`BCSS` and don't go as far as the GEDCOM and ISO 8601 
standards mentioned in a post 
`How to store an incomplete date? <http://weblogs.sqlteam.com/mladenp/archive/2007/02/17/60103.aspx>`_.

Release :lino:`/releases/2011/1120` + upgrade in Eupen.