Comparing Option<T> to null doesn't work as expected about succinct HOT 5 CLOSED

Looking at the code around the == operators for Option<T> and Maybe<T>, I think maybe I'd had at least ten too many beers when writing that stuff! 😨 It looks like a classic example of "just keep adding more crap until the tests pass".

Time for a serious bit of refactoring...

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Accidentally checked in the fix for this with the commit of the 4th May. Comparisons between options, maybes and null are greatly simplified.

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Bug fix included in the v3.0.0 release.

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It's not as simple as it seems.

SQL null comparison rules state that any comparison to null value returns false.
According to SQL rules, null = null check result is false.

It's not clear which null comparison standard is "true".

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It's not clear which null comparison standard is "true".

How is that? Why do we care about SQL rules? In CLR world comparing one null reference to another null reference is determined to return "true" (https://github.com/dotnet/csharplang/blob/master/spec/types.md#the-bool-type).

In the C and C++ languages, a zero integral or floating-point value, or a null pointer can be converted to the boolean value false, and a non-zero integral or floating-point value, or a non-null pointer can be converted to the boolean value true. In C#, such conversions are accomplished by explicitly comparing an integral or floating-point value to zero, or by explicitly comparing an object reference to null.

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