+date:<expr>..! can be used as a shorthand for date:<expr>..<expr>. The
+expansion takes place before interpretation, and thus, for example,
+date:monday..! matches from the beginning of Monday until the end of
+Monday.
+With **Xapian Field Processor** support (see below), non-range
+date queries such as date:yesterday will work, but otherwise
+will give unexpected results; if in doubt use date:yesterday..!
+