Is `timezone` optional? I like it that it has the ability for one to provide it, but not providing it could just use the one the system has been configured to use.
Requiring a timezone seems sensible to me, but I don't understand the choice to make it a required part of the expression, instead of a separate parameter. Most software specifies the timezone separately from the expression (e.g. k8s has separate `schedule` and `timezone` keys).
So many of these restrictions feels arbitrary. Not supporting comments? Why?
Assuming UTC for tz is not weird and cron users expect it,
I guess why even support this specific syntax if the crons need to be edited to fit how this code expects them? There may have been better options if you were going full green field.
> Assuming UTC for tz is not weird and cron users expect it,
That would definitely be weird and unexpected. My crons are interpreted with respect to my system's configured time zone, which seems way more expected than just using UTC.
Taking a datetime and just assuming it's UTC is often a mistake. It's why the TC39 Temporal proposal (overhauling datetimes for Javascript) won't let you silently do it.
Could you elaborate a bit on the issue? I'm not sure you are commenting on cronexpr or other libraries.
In cronexpr, there is no requirement for a timestamp until you'd like to find the next scheduled time, and thus you need to provide a related point.
To decouple with certain datetime lib, I made a `MakeTimestamp` struct which provides multiple constructors. Later, I found it somehow like a function overload :D
