anchor.diff:    ([msg]  (println msg)))
   ----
   
  -This function declares two arities (0 arguments and 1 argument). The 0-argument arity calls the 1-argument arity with a default value to print. We invoke these functions by passing the appropriate number of arguments:
  +This function declares two arities (0 parameters and 1 parameter). The 0-parameter arity calls the 1-parameter arity with a default value to print. We invoke these functions by passing the appropriate number of arguments:
   
   [source,clojure-repl]
   ----
  
positive.code:   (println greeting who))
  ----
  
  This function takes an argument `greeting` and a variable number of arguments (0 or more) that will be collected in a list named `who`. We can see this by invoking it with 3 arguments:
  
  [source,clojure-repl]
  ----
  
negative.code: 
  There is a shorter form for the `fn` anonymous function syntax implemented in the Clojure reader: `#()`. This syntax omits the parameter list and names parameters based on their position.
  
  * `%` is used for a single parameter
  * `%1`, `%2`, `%3`, etc are used for multiple parameters
  * `%&` is used for any remaining (variadic) parameters
  
  Nested anonymous functions would create an ambiguity as the parameters are not named, so nesting is not allowed.
  
  