Method and apparatus for generating recurring events in a calendar/schedule system

An electronic calendar system for displaying a plurality of events to a user, said system comprising:

• a storage device to store an event definition containing a set of recurrence information and anti-event information, wherein said recurrence information comprises an expression that specifies a plurality of events, wherein each of said plurality of events occurs at a particular time, and wherein said anti-event information comprises an expression that specifies that a subset of said plurality of events do not occur at any time;
• means for accessing said recurrence information and said anti-event information in said event definition and for generating a plurality of recurring events and associated dates based upon said recurrence information and said anti-event information as a calendar, wherein said recurring events include only those events of said plurality of events that are not members of said subset of events;
• and
• a display device to display said calendar.

A computer-readable medium carrying one or more sequences of instructions for displaying to a user, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to:

• store recurrence information and anti-event information in an event definition, wherein said recurrence information comprises an expression that specifies a plurality of events, wherein each of said plurality of events occurs at a particular time, and wherein said anti-event information comprises an expression that specifies that a subset of said plurality of events do not occur at any time;
• access said recurrence information and said anti-event information in said event definition;
• generate a plurality of recurring events and associated dates based upon said recurrence information and said anti-event information, wherein said recurring events include only those events of said plurality of events that are not members of said subset of events;
• and
• display a calendar having said plurality of recurring events and associated dates.

An apparatus for determining a plurality of recurring events, said apparatus comprising:

• a database, wherein said database comprises
• a plurality of recurrence expressions, wherein each of said plurality of recurrence expressions specifies a plurality of events, wherein each of said plurality of events occurs at a particular time, and
• a plurality of anti-event expressions, wherein each of said anti-event expressions specifies that a subset of said plurality of events do not occur at any time;
• a processor, wherein said processor is configured to
• access said database to obtain said plurality of recurrence expressions and said plurality of anti-event expressions, and
• generate said plurality of recurring events and associated dates based upon said recurrence expressions and said anti-event expressions, wherein said recurring events include only those events of said plurality of events that are not members of said subset of events.