anchor.diff:              }
   
         section
  -        h1.bullet Let
  -        ul
  +        h1 Let
  +        ul.bullet
             li #[span.token.keyword var] is function scoped
             li #[span.token.keyword let] is block scoped
             li A block is any pair of { }
  
positive.code: 
        section
          h1 Let
          h3.bullet How does var's scoping work?
          ul
            li var is function scoped
  
        section
          h1 Var
  
negative.code:               console.log(a); // 2
              }
  
        section
          h1 Let - Why?
          ul.bullet
            li Principle of Least Privilege
            li If a variable is not used outside of a block of code, don't expose it
  
        section
          h1 Let - Gotchas
          ul.bullet
            li Let is not hoisted like var
            li Because of the way Babel transpiles let, let is hoisted when using Babel
  
        section
          h1 Let - Babel
  
  
  
  
      script(src='build/build.js')
  