let d: int = if (c > a) { 99 } else { 100 };

let add = fn(a,b): int { a + b};
let sub = fn(a,b): int { a - b};
let applyFunc = fn(a: int, b: int ,func: fn(int, int): int): int { func(a,b) };

applyFunc(2, 2, add); // 4
applyFunc(10, 2, sub); // 8

let makeGreeter: fn(str): str = fn(greeting: str): fn(str): str {
    return fn(name: str): str {
        return greeting + " " + name + "!"
    }
};

let hello = makeGreeter("Hello");
hello("John"); // Hello John!

let arr: []int = [1, 2, 3, 4];
len(arr); // 4
len("hello world"); //11

let a: []int = [1, 2, 3, 4];
let b: []int = push(a, 5);

println(a) // [1, 2, 3, 4]
println(b) // [1, 2, 3, 4, 5]

a = rest(a);
println(a) // [2, 3, 4]
a = rest(a);
println(rest(a)) // [3, 4]

let even: []int = fn(): []int {
    let arr: []int = [];
    for (i in 0..10) {
        if i % 2 == 0 {
            arr = push(arr, i);
        }
    }
    return arr;
}()

println("list of even number:", even)

let fib: float = fn(n): float {
    if n <= 1 {
        return n;
    };
    return fib(n-1) + fib(n-2);
}

// create map function with built in function
let map = fn(arr, f) {
    let iter = fn(arr, accumulated) {
        if (len(arr) == 0) {
            accumulated
        } else {
        iter(rest(arr), push(accumulated, f(arr[0])));
        }
    };
    iter(arr, []);
};

let a = [1, 2, 3, 4];
let double = fn(x) { x * 2 };
map(a, double); //[2, 4, 6, 8]

// create reduce function with built in function
let reduce = fn(arr, initial, f) {
    let iter = fn(arr, result) {
        if (len(arr) == 0) {
            result
        } else {
            iter(rest(arr), f(result, arr[0]));
        }
    };
iter(arr, initial);
};

let sum = fn(arr) {
    reduce(arr, 0, fn(initial, el) { initial + el });
};
sum([1, 2, 3, 4, 5]); // 15

for {
    // action
};

let x: int = 0;
for (x < 10) {
    x = x + 1; // TODO: implement "+=", "-="
};

for (i in 0..10) {
    println(i);
};

let myHash: = {"name": "Jimmy", "age": 72, "band": "Led Zeppelin"};
myHash["name"] // Jimmy
myHash["age"] // 72

let Event: enum = enum(add, remove, create, key_press(str))
println(Event.add);
println(Event.remove);
println(Event.created);

let Option = enum(some(num), none)

Option.some(1)


let age: num = 2;
let name: str = "bola";