/Prelude-v21.1.0/Optional/unzip.dhall

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Unzip an Optional value into two separate Optional values

Examples

  unzip Text Bool (Some { _1 = "ABC", _2 = True })
≡ { _1 = Some "ABC", _2 = Some True }
  unzip Text Bool (None { _1 : Text, _2 : Bool })
≡ { _1 = None Text, _2 = None Bool }

Source

--| Unzip an `Optional` value into two separate `Optional` values
let unzip
: ∀(a : Type) →
∀(b : Type) →
Optional { _1 : a, _2 : b } →
{ _1 : Optional a, _2 : Optional b }
= λ(a : Type) →
λ(b : Type) →
λ(xs : Optional { _1 : a, _2 : b }) →
{ _1 =
merge
{ Some = λ(x : { _1 : a, _2 : b }) → Some x._1, None = None a }
xs
, _2 =
merge
{ Some = λ(x : { _1 : a, _2 : b }) → Some x._2, None = None b }
xs
}

let example0 =
assert
: unzip Text Bool (Some { _1 = "ABC", _2 = True })
≡ { _1 = Some "ABC", _2 = Some True }

let example1 =
assert
: unzip Text Bool (None { _1 : Text, _2 : Bool })
≡ { _1 = None Text, _2 = None Bool }

in unzip