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+# RETRO Cross Reference
+
+Definitions
+-----------
+RETRO    :name ;
+ANS      : name ;
+
+
+Numbers
+-------
+RETRO    #100  #-12
+ANS      100   -12
+
+
+Characters
+----------
+RETRO    $A      $D
+ANS      CHAR A  CHAR D
+
+RETRO    :foo $A ;
+ANS      : foo [CHAR] A ;
+
+
+Comments
+--------
+RETRO    (This_is_a_comment)
+ANS      ( This is a comment )
+
+
+Pointers
+--------
+RETRO    &Compiler
+ANS      ' Compiler
+RETRO    :foo &Heap ;
+ANS      : foo ['] Heap ;
+
+
+Conditionals
+------------
+RETRO    (flag) [ 'TRUE ] if
+ANS      ( flag ) IF s" TRUE" THEN
+
+RETRO    (flag) [ 'FALSE ] -if
+ANS      ( flag ) NOT IF s" FALSE" THEN
+
+RETRO    (flag) [ 'TRUE ] [ 'FALSE ] choose
+ANS      ( flag ) IF s" TRUE" ELSE s" FALSE" THEN
+
+RETRO conditionals can be used outside of definitions, ANS ones can not.