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Ah nice it solves the Liskov violation that the standard library has. In the standard library, dates can be compared with <, and datetimes are dates. But compare a datetime with a date with <, and you get an error. This drove me nuts at work recently.

I wonder what benefits this choice has that outweigh the risks of this behavior.

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What would you do about equality comparisons?

The author wrote a blog post describing that the problem is datetime inherits from date when it shouldn’t. The fact they do but can’t be compared is a compounding of the problem with hidden bugs

What do you expect? There are so many ways to handle this behvaiour it's pretty obvious why this is not allowed. Do you take datetime.date and then compare? Do you assume all dates are datetimes at midnight?

The issue isn't that the comparison should be valid, the issue is that datetimes should not be dates. At best, there is a "has a" relationship, but there shouldn't be an "is a" relationship.

I think wesselbindt meant that datetimes should not inherit from dates.

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