infinite loop on SUNDAY 2.30

[bethard]

The code goes into an infinite loop when trying to parse "SUNDAY 2.30".

The problem is that this is getting parsed as:

FindLater(Present,Map(DayOfWeek -> 7, MonthOfYear -> 2, DayOfMonth -> 30))

That is, Sunday, the 30th of February. It then goes into an infinite loop trying to search for an impossible day. You can get a failure instead of an infinite loop by deleting this line from the grammar:

[Nil] ||| . ||| ||| 1.0

Avoiding this infinite loop would require somehow recognizing that the field values MonthOfYear -> 2 and DayOfMonth -> 30 cannot be combined. I'm not sure how to detect that.