SRTP-Active-Patterns.fs

SRTP-Active-Patterns.fs

module NameOps =
  let inline (|HasName|) x = (^a : (member Name : string) x)
  let inline (|HasAge|) x = (^a : (member Age : int) x)
  let inline (|IsIdentifyable|) (HasName name & HasAge age) = name, age

  let inline doWithIsIdentifyable (IsIdentifyable (name,age)) =
    printfn $"{name} - {age}"
type Dog = {
  Name : string
  Age: int
  FavoriteChewToy : string
}

type Cat = {
  Name : string
  Age : int
  FeedingTime : System.DateTime
}

let dog = {
  Name = "Fido"
  Age = 3
  FavoriteChewToy = "My shoes"
}

let cat = {
  Name = "Mr Muffin"
  Age = 30
  FeedingTime = System.DateTime.Now
}


NameOps.doWithIsIdentifyable dog
NameOps.doWithIsIdentifyable cat