Example reveal-remark presentation

include code samples like this

ts
let a = 1;
 
a = a + '2';
Type 'string' is not assignable to type 'number'.2322Type 'string' is not assignable to type 'number'.

use twoslash queries for type callouts

ts
const dishes = ["pasta", "pizza", "lasagne"];
 
const favourite = dishes[2];
         
const favourite: string

Include other languages

rs
#[derive(Debug)]
struct Rectangle {
    width: u32,
    height: u32,
}
impl Rectangle {
    fn square(size: u32) -> Rectangle {
        Rectangle { width: size, height: size }
    }
    fn area(&self) -> u32 {
        self.width * self.height
    }
    fn can_hold(&self, other: &Rectangle) -> bool {
        &self.width >= &other.width && &self.height >= &other.height
    }
}