service ServiceWithDefaultId("defaultId"):
    hello(s: string)

service ServiceWithOUTDefaultId:
    hello(s: string)

service MoreMembers:
    member1()
    member2(s1: string)
    member3(s1: string, s2: string)
    member4(s1: string, s2: string, i: i32) -> i32
    member5(s1: string, s2: string, i: i32) -> i32

func f1(callback: string, i32 -> ()):
    callback("hello, world", 42)

func f2(num: i32, callback: string, i32 -> ()):
    callback("hello, world", 42)

func f3(num: i32, callback: string, i32 -> ()) -> string:
    callback("hello, world", 42)
    <- "hello world"

func callBackZeroArgs(callback: -> ()):
    callback()