struct Buffer[T] {
    size int
mut:
    content []T
}

pub fn create_buffer[T](size int) Buffer[T] {
    return Buffer[T]{
        size:    size
        content: []T{}
    }
}

pub fn (mut b Buffer[T]) write(value T) {
    b.content.prepend(value)
}

fn test_main() {
    mut buffer := create_buffer[int](3)
    buffer.write(1)
    assert buffer.content[0] == 1
}