anchor.diff:  
   (define-pattern-formatter (#\< #\>)
     "Wrap content inside into PPRINT-LOGICAL-BLOCK"
  -  (declare (ignore fmt-info))
     (pprint-logical-block (stream nil)
  -    (funcall wrap stream logger log-level log-func)))
  +    (if (format-empty-skip fmt-info) 
  +        (let ((*print-pretty* t)) 
  +          (funcall wrap stream logger log-level log-func))
  +        (funcall wrap stream logger log-level log-func))))
   
   (define-pattern-formatter (#\> #\<)
     "Wrap content inside with *PRINT-PRETTY* bound to NIL"
  
positive.code:                          (compile-pattern-format pattern idx stopchar)
                         (setq idx newidx)
                         (add-formatter (lambda (stream fmt-info logger level log-func)
                                          (funcall formatter stream fmt-info logger level log-func wrap))))))
                 (setq state :normal
                       minlen 0
                       maxlen nil
  
negative.code: 
     PRETTY-PRINTER CONTROL
  
     %< and %> the formatting inside is wrapped into
     PPRINT-LOGICAL-BLOCK, the value of *PRINT-PRETTY* is not changed.
  
     The colon flag %:< %> in addition to wrapping whats inside in
     PPRINT-LOGICAL-BLOCK will also bind *PRINT-PRETTY* to T
  
     %> and %< is the opposite pair, *PPRINT-PRETTY* is unbound inside
  
     %_ conditional newline, issues (PPRINT-NEWLINE :linear)
     %:_ conditional newline, issues (PPRINT-NEWLINE :fill)
  