koobas.hobune.stream
HashSet missing most methods
I'm trying to use HashSet but whenever I try to use any of the built in methods besides Add or Remove, I'm met with an error: ``` Type HashSet<ChunkType>' does not contain a definition for UnionWith' and no extension method UnionWith' of type HashSet' could be found. Are you missing an assembly reference? ``` I didn't forget to include System.Collections.Generic and the compiler/IDE (Visual Studio) still recognizes the HashSet type. I'm having issues with UnionWith, IntersectWith and RemoveWhere specifically, but none of the other methods are working either.
