Query Directives
A query directive transforms a list of zettel identifier into a list of zettel identifiert. It is only valid if a list of zettel identifier is specified at the beginning of the query expression. Otherwise the text of the directive is interpreted as a search expression. For example, CONTEXT is interpreted as a full-text search for the word “context”.
Every query directive therefore consumes a list of zettel, and it produces a list of zettel according to the specific directive.