anchor.diff:  ----
   
   Let's build your Node project. We can specify that we want to generate code for
  -a specific JavaScript target via `-t` for `--target`. `-t` defaults to browser.
  -Other valid but less common options are `nashorn` and `rhino`. We're also using
  -`-o` for specifying the `--output-to` file:
  +a specific JavaScript target via `-t` for `--target`. If no `-t` is supplied,
  +ClojureScript generates code for browsers. Other valid but less common options
  +are `nashorn` and `rhino`. We're also using `-o` for specifying the
  +`--output-to` file:
   
   [source,bash]
   ----
  
positive.code: optimizations. While advanced optimizations does apply performance
  related optimizations, these are now largely obviated by optimizations
  present in modern JavaScript virtual machines like V8, SpiderMonkey, and
  JavaScriptCore. For Node.js, `:simple` or `:none` optimizations suffice
  and using them removes the need for extra steps like supplying an
  externs file.
  ====
  
  [[node.js-repl]]
  
negative.code: `-m`, which is short for `--main` invokes a Clojure function, in this case
  `cljs.main`. The `cljs.main` function supports a variety of command line
  arguments to specify common tasks. We're using `-c` for `--compile` to specify
  that we want to compile the `hello-world.core` namespace. This is followed by
  `-r` for `--repl` to say that we want a REPL to start immediately when compilation
  completes.
  
  Your default web browser will open to a page that looks like the following:
  