Use c# 8.0 and enable nullable reference

You can enable c# 8.0 and Nullable reference types with dotnet core 2.2 . Just add lines below to the project file:

<PropertyGroup>
  <LangVersion>8.0</LangVersion>
  <Nullable>enable</Nullable>
  <!-- NullableContextOptions will be replaced by Nullable in dotnet core 3.0 -->
  <NullableContextOptions>enable</NullableContextOptions>
</PropertyGroup>

Handling nullable is a very important part of this lib. I with it could work smoothly with the new “Nullable reference types”. And I with this lib can support something like Option<string?>.

[louthy]

Yes, it’s on my list 😃

[StefanBertels]

Just my 2 pence: I like the library features for Option<T> especially things like LINQ support (bind). C# 8 will make nullables safer but I personally think that I want to stay with Option<T>. This way I can use e.g. Sequence and Traverse in a very generic way.

I guess it will be very hard to make T? work like Option<T>. Maybe we could allow implicit casting from T? to Option<T> and maybe back (?).