[Feature] Introduce a task-based API and remove Result<'T, 'E> API friction

This is an attempt to tackle #64 right now, the functions Sql.execute, Sql.executeRow, Sql.executeNonQuery etc. return data in the form of Async<Result<'SomeType, exn>>

This is fine in many cases but it can cause friction when:

• You don’t want Result and instead choose to try ... catch the SQL code only on rare occasions
• You are working with task (for example in Saturn/Giraffe) and don’t want the syntax and performance overhead of converting between async and task

I propose to fix the problems above by introducing mutually exclusive namespaces within this same nuget package that offers different return types BUT with the exact API of the Sql functions:

• Npgsql.FSharp stays the same and continue to return Async<Result<'T, exn>> (package stays backward-compatible without breaking changes)
• Npgsql.FSharp.NoResult exposes API functions that return Async<'T>
• Npgsql.FSharp.Tasks exposes API functions that return Task<'T> with the help of Ply

Yes, the downside is of course the duplication of code in each namespace but I think it is worth the effort of removing as much overhead as possible and of course we can extract the common parts in a module (the RowReader for example).

What do you think @aspnetde @TheAngryByrd @baronfel @ninofloris

[Zaid-Ajaj]

As of v3.12 the library has implemented the namespace Npgql.FSharp.Tasks which offers the exact same API but with tasks and without Result, I haven’t gotten around to fully test it but in principle it should work 🤞 can you please give it a try and let me know how it goes? I have also updated the README docs to reflect the changes

@vilinski Latest has now updated Npgsql to v5.0 and all existing tests worked without changes 😄

[aspnetde]

That’s great news! I will give it a try as soon as possible.