Set record property when creating instance

Question

I have a record type

type Record = { Start: DateTime; End: DateTime; Duration: TimeSpan }
let record = { Start = DateTime.Now; End = DateTime(2021,12,1) }

This code won't compile as there's no assignment given for field Duration.

Is it possible to calculate Duration in the type definition instead of assigning it?

Answer 1

Solved it:

type Record = { Start: DateTime; End: DateTime; }
with
  member this.Duration = this.End - this.Start

let record = { Start = DateTime.Now; End = DateTime(2021,12,1) }