struct Context {
}

struct Input {
}

struct Block {
    x int
    y int
mut:
    children []Element
}

type Element = Block | Input

fn (input Input) draw(mut ctx Context, x int, y int) {}

fn (block Block) draw(mut ctx Context, x int, y int) {
    for child in block.children {
        child.draw(mut ctx, block.x + x, block.y + y)
    }
}

fn (elt Element) draw(mut ctx Context, x int, y int) {
    $for T in Element.variants {
        if elt is T {
            elt.draw(mut ctx, x, y)
            return
        }
    }
}

fn test_main() {
    assert true
}