anchor.diff:      here h# 2000 w,
   ;
   
  -header-imm then
  +header-imm then     ( addr -- )
   : tthen
       here 2/
       swap +!
  
positive.code:     leaves _!
  ;
  
  : (?do)  ( start-limit -- start-limit start!=limit )
      d# 0 over=
  ;
  
  header-imm ?do
  :noname
      do-common
      ['] (?do) compile,
      tif leave, tthen
      tbegin
      inline: >r
  ;
  
  \ Finish compiling DO..LOOP
  
negative.code: header-imm do
  :noname
      do-common
  : dotail
      tbegin
      inline: >r
  ;
  