v0.4.0

Added

• Introduced new WeekdayModifier variant "Last" to select the last occurrence of some weekday, e.g. "at 6 PM (last Monday)".
• Added MultiSchedule to accomodate a combination of several distinct Schedules.
• Added cron_lingo::error::Error::UnexpectedEndOfInput.
• Added cron_lingo::error::Error::Syntax and cron_lingo::error::SyntaxError.

Changed

• Renamed cron_lingo::error::InvalidExpression to simply cron_lingo::error::Error.
• Expressions must now be parsed separately using from_str but may then be combined together with std::ops::Add or added to an existing MultiSchedule using std::ops::AddAssign.
• Iterator of Schedule or MultiSchedule is now fallible (next() returns Option<Result<time::OffsetDateTime, cron_lingo::error::Error>) as the retrieval of the local offset may fail.
• Creation of said iterators via Schedule::iter() or MultiSchedule::iter() is now fallible as well for the same reason.
• Moved from time v0.2.22 to v0.3. Compile flag is needed in order to avoid runtime errors when the local offset is retrieved internally: RUSTFLAGS="--cfg unsound_local_offset" cargo build. The compile flag may be omitted when your application is single-threaded.

Removed

• Removed variants DuplicateInput and IllogicalWeekdayCombination from error enum as the occurrence of duplicates et al. does not prevent correct computation of the next upcoming date.