Is there a standard body or a specific normative way how time-related things should be implemented in practice (like ICU for Unicode-related tasks) or is this currently a "best-effort", depending on how much effort, time and money language and library implementers want to spend?
Is there a specific and complete implementation which could serve as a example for how time-related things should be handled?
Which existing library would you consider as a bad, a decent or a good example?