approved, one thing remained unclear to me from description, an "implicit conversion" is a "from -> to" from bindings (I would say this is an "explicit conversion"). Also "from -> to" and "to -> from" are two different kinds of conversions.

..

ok sounds good

Translation approved

Approved

that's a major spec update, all languages should be revisited .. who changed the spec after 1000's of submissions anyway

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Thank you! As I said, this might invalidate some solutions, including my old one and the top solution (only because it orders before selecting, which is wrong). A lot of other solutions remain good to go.

Approved.

450 random tests for Python (475 for C#) + a little bit of fixed tests. The toughest are of course last 50 ( or 75) tests - 64bit numbers.

Hats off to you for solving this one!!!!!! Well done! m(_ _)m

ad 2: could even have infixl and infixr for left and right associativity ( with precedences ).

room for a sequel?

ETA: created and published

I've had a think and, having thunk, I've removed the closed form, but also amended the description to make it clear that such a thing exists.

Appreciate the feedback!