> Gleam's labelled arguments are AFAIK a unique feature OCaml also does this: # let foo ~bar:baz = baz + 42;; val foo : bar:int -> int = <fun> # f

> Gleam's labelled arguments are AFAIK a unique feature OCaml also does this: # let foo ~bar:baz = baz + 42;; val foo : bar:int -> int = <fun> # foo ~bar:12765;; - : int = 12807 What I really enjoyed was its parameter forwarding, which is available in some languages for records: # let bar = 42;; val bar : int = 42 # foo ~bar;; - : int = 84 Works similarly for optional values: # let test ?(arg=5) () = arg;; val test : ?arg:int -> unit -> int = <fun> # let arg = None;; val arg : 'a option = None # test ?arg ();; - : int = 5 And if you used ~arg, it would be a non-optional parameter: # let arg = 5;; val arg : int = 5 # test ~arg ();; - : int = 5 Overall pretty spiffy. Partial application also works here nicely, but it does cause some trouble with optional arguments :/. For example, here "test" needs to have a final argument () so the optional parameter can be erased: # test;; - : ?arg:int -> unit -> int = <fun> # test ();; - : int = 5