diff options
Diffstat (limited to 'pkgs/profpatsch/dhallsh/List/filterOptional.dhall')
| -rw-r--r-- | pkgs/profpatsch/dhallsh/List/filterOptional.dhall | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/pkgs/profpatsch/dhallsh/List/filterOptional.dhall b/pkgs/profpatsch/dhallsh/List/filterOptional.dhall new file mode 100644 index 00000000..810599b0 --- /dev/null +++ b/pkgs/profpatsch/dhallsh/List/filterOptional.dhall @@ -0,0 +1,23 @@ +let filterOptional + : ∀(a : Type) → ∀(b : Type) → (a → Optional b) → List a → List b + = λ(a : Type) + → λ(b : Type) + → λ(f : a → Optional b) + → λ(l : List a) + → List/build + b + ( λ(list : Type) + → λ(cons : b → list → list) + → λ(nil : list) + → List/fold + a + l + list + ( λ(x : a) + → λ(xs : list) + → Optional/fold b (f x) list (λ(opt : b) → cons opt xs) xs + ) + nil + ) + +in filterOptional |