- DOM::get now returns the input name by default, rather than "", which
was the cause of many filter elements not working.
- Modified Variant to have no private data, which means fewer copies of
Variants and less code.
- Eliminated Variant::operator^ - not needed.
- Filter processing short-circuits if there is no filter.
- Variant code was not only incomplete, but very broken. It should not have
been used. It still doesn't handle dates and durations.
- Converted all logical and relational Variant operators to return Boolean
values.
- Stack size is now checked for every operator.
- All operators implemented (without any advanced special case handling) except
%, ~ and !~.
- Added lazy DOM expansion at the last possible moment.
- Implemented Expression::create_variant to create appropriate Variant instances
based on categorized and inferred type.
- Removed Variant math functions. No point.
- Debug code left in place for now.
- Added new src/commands and src/columns intermediate libs.
- Began implementation of the first Command object.
- Began implementation of the first Column object.
- TDB2, Variant updates.
