This is a a simple object that has the operator and param for a filter.
Optional
Ignore Blank: a blank passes before anything is asked. See ICondition.isIncludeBlanks.
false, and a blank is then a value the condition judges.
false
The root condition's alone. A combinator's child carries none: one given is not read, and is not written back.
The operator.
The param for the condition.
This is operator-specific and not all operators require param.
The selector.
This is a a simple object that has the operator and param for a filter.