blog/content/decks/test.html

<section>
  <h2>Object (dis)orientation</h2>
  <h6>How to survive a "post-OO" world</h6>
</section>
<section>
  <section>Class/Inheritance has challenges</section>
  <section>
    Combining Data + Code
    <pre><code data-trim data-noescape data-line-numbers="5|7-9">
		class MyBase {
			protected:
				int useless;
			public:
				virtual void makeSound() = 0;

				virtual int get_thing() {
					return -1;
				};
		};
		</code></pre>
    <p class="fragment">
      You have to know if this is an "interface", abstract class, or regular
      class.
    </p>
    <small class="fragment"
      >(it's an abstract class, since <code>makeSound</code> is pure
      virtual)</small
    >
  </section>
  <section>
    <p>A class can be one of many things</p>
    <ul>
      <li>Interface - abstract class with no members, and purely virtual</li>
      <li>Abstract Class - class with <em>some</em> pure virtual methods</li>
      <li>
        "Regular" Class - class that is standalone and is fully implemented
      </li>
    </ul>
    <small class="fragment"
      >These concepts all exist under the <code>class</code> keyword
    </small>
  </section>
</section>
<section>
  In Rust, you trade <em>Inheritance</em> for <em>Traits</em> and
  <em>Types</em>.
</section>

<section>
  <section>
    <p>Traits are <em>Interfaces</em></p>
    <pre><code data-trim data-noescape>
	pub trait Mammal {
		fn get_temp(&self) -> i32;
	}
	</code></pre>
  </section>
  <section>
    <p>... that are explicitly implemented</p>
    <pre><code data-trim data-noescape>
		pub struct Cat {
			age: i32,
			outdoor: bool,
		}
		impl Mammal for Cat {
			fn get_temp(&self) -> i32 {
				if self.outdoor {
					65
				} else {
					72
				}
			}
		}
		</code></pre>
  </section>
  <section>
    <p>And can be used statically <em>or</em> dynamically!</p>
    <pre><code data-trim>
		fn static_mammal&lt;T: Mammal&gt;(m: T) {
			// the type of T must be known at compile time.
		}
		fn dyn_mammal(m: &dyn Mammal) {
			// This uses a vtable to dispatch at runtime.
		}
		</code></pre>
  </section>
</section>