https://fsharp.github.io/fsharp-core-docs/reference/fsharp-collections-seqmodule.html
https://fsharp.github.io/fsharp-core-docs/reference/fsharp-collections-setmodule.html
https://fsharp.github.io/fsharp-core-docs/reference/fsharp-collections-arraymodule.html
https://docs.microsoft.com/en-us/dotnet/standard/base-types/regular-expressions?redirectedfrom=MSDN
install ionide-paket for nuget package completions
use expecto for testing like I want in Rust