anchor.diff:  ----
   
   
  -== Tuples
  +== Tuple (data structure)
   
   The *tuple* is the next data structure we'll explore.
   
  
positive.code: }
  ----
  
  == Variables with the `let` function
  
  The `let` function sets *variables* and runs a Streaming Expression that references the variables. The `let` funtion can be used to
  write small statistical programs.
  
negative.code: }
  ----
  
  == Array (data structure)
  
  The first data structure we'll explore is the *array*.
  
  