It would be most useful to be able to have the ability to distinguish between a
number and a boolean for a cell values in calc. Currently the only boolean
support is in the form of the TRUE() & FALSE() functions. This presents a number
of limitations 
* When these functions are evaluated from the api there doesn't seem to be a way
to distinguish between 0/1 and true/false as only a number can be retrieved (
table::CellContentType only distinguishes between number, string & function :-( ). 
* Granted in the code it is possible to distinguish between a number and a
boolean via the cell format attributes. This really isn't strong enough... for
example if you paste-special ( values only, a common operation ) a cell with a
boolean value the formating is lost. 
* Interfacing with oobasic ( user defined functions ) is also a pain as calc
boolean and basic's built-in boolean type evaluate differently ( oobasic
true/false value is determined by an expression that evaluates -1, 0
respectively, calc uses 0/1 symantics ) and you can't for example test the
boolean value of a cell directly. When you consider that its possible to link
form controls ( e.g. checkboxes, optionbuttons )to cells which modify those
cells values as a boolean and then want to drive code using those controls its
obvious that the situation is far from ideal. 
* From an interoperability point of view this also presents difficulties as
Excel has a built in boolean primitve which acts the same as oobasics boolean
primitive.

Thoughts?