anchor.diff:  \ block for WORD.
   : PARSE  \ ( char "ccc<char>" -- c-addr u )                     ( core ext )
       0 SWAP    \ 0 counter if needed
  -    PARSE-DO
  -      I @ OVER BL-TEST
  -        IF DROP   I SOURCE DROP -   SWAP LEAVE THEN
  +    SOURCE + PARSE-POS
  +    DO
  +      I C@ OVER ?DELIM
  +        IF DROP I SOURCE + - SWAP LEAVE THEN
       LOOP
  -    DROP  \ delimiter
  +    DROP
       PARSE-POS SWAP DUP >IN +! ;
   
   \ Comments
  -: (  41 PARSE DROP DROP ; IMMEDIATE
  +: (  41 PARSE 2DROP ; IMMEDIATE
   
   \ Skip delimiter characters from the input stream.
   : SKIP  ( char "<chars>" -- )
  -    PARSE-DO
  -      I @ OVER BL-TEST 0= IF LEAVE THEN
  +    SOURCE + PARSE-POS
  +    DO
  +      I @ OVER ?DELIM 0= IF LEAVE THEN
         >IN 1+!
       LOOP
       DROP ( delimiter )
  
positive.code: : COMPILE,  ( xt -- )                                           ( core-ext )
      , ;
  
  
  : POSTPONE
      BL WORD FIND
      IF COMPILE, ELSE ABORT"  THEN
  ; IMMEDIATE
  
  : ?PAIRS  - IF ABORT" unmatched conditionals" THEN ;
  
  \ Conditionals
  : IF    HERE POSTPONE JUMP-FALSE 0 COMPILE, 2 ; IMMEDIATE
  : ELSE  2 ?PAIRS HERE DUP ROT BACKPATCH POSTPONE JUMP 0 COMPILE, 2 ; IMMEDIATE
  : THEN  2 ?PAIRS HERE SWAP BACKPATCH ; IMMEDIATE
  
  \ Colon definitions
  : :  CREATE ] ;
  : ;  POSTPONE EXIT SMUDGE [ ; IMMEDIATE
  
  
  
  
negative.code: 
  : PARSE-POS  \ ( -- caddr )
      SOURCE DROP >IN @ + ;
  
  32 CONSTANT BL
  
  