vasily-kirichenko

fib(0) -> 0;
fib(1) -> 1;
fib(N) when N > 0 -> fib(N - 1) + fib(N - 2).

lists:foreach(fun(N) -> io:format("n=~p => ~p~n", [N, fib(N)]) end, lists:seq(0, 39)).

vasily-kirichenko

let rec fib n =
    match n with
        |0|1 -> n
        |x when x > 0 -> fib(x - 1) + fib(x - 2)

for x in 0..39 do
    printfn "fib(%d) = %d" x (fib x)

vasily-kirichenko

type BinaryTree =
    |Node of obj * BinaryTree * BinaryTree
    |Empty
    member tree.Traverse f =
        match tree with
            |Node(data, l, r) -> 
                f data
                l.Traverse f
                r.Traverse f
            |Empty -> ()

vasily-kirichenko

def fib(n)
{
    |0|1 => n
    |_ => fib(n - 1) + fib(n - 2)
}
        
foreach (i in $[0..39])
    WriteLine("fib({0}) = {1}", i, fib(i));

vasily-kirichenko

public macro not_null(obj)
syntax ("not_null", obj)
{
    def var_name = $"$obj";
    <[ 
        when ($obj == null)
            throw System.ArgumentNullException($var_name);
        $obj;
    ]>
}

vasily-kirichenko

public macro not_null(obj)
syntax ("not_null", obj)
{
    def var_name = $"$obj";
    <[ 
        when ($obj == null)
            throw System.ArgumentNullException($var_name);
        $obj;
    ]>
}

vasily-kirichenko

class Person
{
    public Name: string;
            
    public this(name: string)
    requires name != null
    {
        Name = name;
    }
}

vasily-kirichenko

class Person
{
    public Name: string;
    public Age: int;
	
    public this(requires (name != null && name.Length > 0) name: string,
                requires (age > 0) age: int)
    {
        Name = name;
        Age = age;

vasily-kirichenko

class Person
{
    public Name: string;
           
    public this([NotNull] name: string)
    {
        Name = name;
    }
}

vasily-kirichenko

(defn fib [n]
  (if (< n 2)
    n
    (+ (fib (- n 1))
       (fib (- n 2)))))

(time
  (doseq [n (range 40)]
    (prn (str "Fib(" n ") = " (fib n)))))