anchor.diff:     ())
   
     (command
  -   (simple-command)
  +   (compound-command redirect-list)
      (compound-command)
  -   (compound-command redirect-list)
  -   (function-definition))
  +   (function-definition)
  +   (simple-command))
   
     (compound-command
      (brace-group)
  
positive.code:    ())
  
    (if-clause
     (if-word compound-list then compound-list else-part fi)
     (if-word compound-list then compound-list fi))
  
    (else-part
     (elif compound-list then else-part)
     (else compound-list))
  
    (while-clause
  
negative.code:    ())
  
    (pipeline
     (bang pipe-sequence)
     (pipe-sequence))
  
    (pipe-sequence
     (command pipe-sequence-tail))
  