B.  UNCONTROLLED REFERENCE WORDS




                      APPENDIX B.  UNCONTROLLED REFERENCE WORDS


          The Uncontrolled Reference Word Set contains glossary definitions
          which are included for public reference of words that have past
          or present usage and/or are candidates for future
          standardization.  No recommendation is made that these words be
          included in a system.

          No restrictions are placed on the definition or usage of
          uncontrolled words.  However, use of these names for procedures
          differing from the given definitions is discouraged.

          !BITS        16b1 addr 16b2 --                      "store-bits"
               Store the value of 16b1 masked by 16b2 into the equivalent
               masked part of the contents of addr, without affecting bits
               outside the mask.

          **           n1 n2 -- n3                                 "power"
               n3 is the value of n1 to the power n2.

          +BLOCK       w -- u                                 "plus-block"
               u is the sum of w plus the number of the block being
               interpreted.

          -'           -- addr false                           "dash-tick"
                       -- true                       
               Used in the form:                     
                       -' <name>                     
               Leave the parameter field of <name> beneath zero (false) if
               <name> can be found in the search order; leave only true if
               not found.

          -MATCH       addr1 +n1 addr2 +n2 -- addr3 flag      "dash-match"
               Attempt to find the +n2-length text string beginning at
               addr2 somewhere in the +n1-length text string beginning at
               addr1.  Return the last+1 address addr3 of the match point
               and a flag which is zero if a match exists.

          -TEXT        addr1 +n1 addr2 -- n2                   "dash-text"
               Compare two strings over the length +n1 beginning at addr1
               and addr2.  Return zero if the strings are equal.  If
               unequal, return n2, the difference between the last
               characters compared:  addr1(i) - addr2(i).











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          B.  UNCONTROLLED REFERENCE WORDS


          /LOOP        +n --                         C,I         "up-loop"
                       sys --   (compiling)          
               A do-loop terminating word.  The loop index is incremented
               by the positive value +n.  If the unsigned magnitude of the
               resultant index is greater than the limit, then the loop is
               terminated, otherwise execution returns to the corresponding
               DO .  The comparison is unsigned magnitude.  sys is balanced
               with its corresponding DO .  See:  DO

          1+!          addr --                            "one-plus-store"
               Add one to the 16-bit contents at addr.

          1-!          addr --                           "one-minus-store"
               Subtract one from the 16-bit contents at addr.

          ;:           -- addr                       C,I"semi-colon-colon"
               Used to specify a new defining word:  
                       : <namex> <name>              
               When <namex> is executed, it creates an entry for the new
               word <name>.  Later execution of <name> will execute the
               sequence of words between ;: and ; , with the address of the
               first (if any) parameters associated with <name> on the
               stack.

          ;S           --                            Interpret only"semi-s"
               Stop interpretation of a block.

          <>           w1 w2 -- flag                           "not-equal"
               flag is true if w1 is not equal to w2.

          <BUILDS      --                                         "builds"
               Used in conjunction with DOES> in defining words, in the
               form:   
                       : <namex> ... <BUILDS ... DOES> ... ;              
               and then:                             
                       <namex> <name>                
               
               When <namex> executes, <BUILDS creates a dictionary entry
               for the new <name>.  The sequence of words between <BUILDS
               and DOES> established a parameter field for <name>.  When
               <name> is later executed, the sequence of words following
               DOES> will be executed, with the parameter field address of
               <name> on the data stack.

          <CMOVE       addr1 addr2 u --                   "reverse-c-move"
               A synonym for CMOVE> .

          ><           16b1 -- 16b2                            "byte-swap"
               Swap the high and low bytes within 16b1.

          >MOVE<       addr1 addr2 u --                   "byte-swap-move"
               Move u bytes beginning at addr1 to the memory beginning at
               addr2.  During this move, the order of each byte pair is
               reversed.



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          B.  UNCONTROLLED REFERENCE WORDS


          @BITS        addr 16b1 -- 16b2                      "fetch-bits"
               Return the 16-bits at addr masked by 16b1.

          AGAIN        --                            C,I                  
                       sys --   (compiling)          
               Effect an unconditional jump back to the start of a BEGIN-
               AGAIN loop.  sys is balanced with its corresponding BEGIN .
               See:  BEGIN

          ASCII        -- char                       I,M          "as-key"
                       --                            (compiling)          
               Used in the form:                     
                       ASCII ccc                     
               where the delimiter of ccc is a space.  char is the ASCII
               character value of the first character in ccc.  If
               interpreting, char is left on the stack.  If compiling,
               compile char as a literal so that when the colon definition
               is later executed, char is left on the stack.

          ASHIFT       16b1 n -- 16b2                            "a-shift"
               Shift the value 16b1 arithmetically n bits left if n is
               positive, shifting zeros into the least significant bit
               positions.  If n is negative, 16b1 is shifted right; the
               sign is included in the shift and remains unchanged.

          B/BUF        -- 1024                          "bytes-per-buffer"
               A constant leaving 1024, the number of bytes per block
               buffer.

          BELL         --                            
               Activate a terminal bell or noise-maker as appropriate to
               the device in use.

          CHAIN        --                            M                    
               Used in the form:                     
                       CHAIN <name>                  
               Connect the CURRENT vocabulary to all definitions that might
               be entered into the vocabulary <name> in the future.  The
               CURRENT vocabulary may not be FORTH or ASSEMBLER .  Any
               given vocabulary may only be chained once, but may be the
               object of any number of chainings.  For example, every user-
               defined vocabulary may include the sequence:               
                       CHAIN FORTH

          CONTINUED    u --                          M                    
               Continue interpretation at block u.

          CUR          -- addr                       
               A variable pointing to the physical record number before
               which the tape is currently positioned.  REWIND sets CUR=1.

          DBLOCK       ud -- addr                    M           "d-block"
               Identical to BLOCK but with a 32-bit block unsigned number.




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          B.  UNCONTROLLED REFERENCE WORDS


          DPL          -- addr                       U             "d-p-l"
               A variable containing the number of places after the
               fractional point for input conversion.

          FLD          -- addr                       U             "f-l-d"
               A variable pointing to the field length reserved for a
               number during output conversion.

          H.           u --                          M             "h-dot"
               Output u as a hexadecimal integer with one trailing blank.
               The current base is unchanged.

          I'           -- w                          C           "i-prime"
               Used within a colon definition executed only from within a
               do-loop to return the corresponding loop index.

          IFEND                                      Interpret only"if-end"
               Terminate a conditional interpretation sequence begun by
               IFTRUE .

          IFTRUE       flag --                    Interpret only "if-true"
               Begin an:                             
                       IFTRUE ... OTHERWISE ... IFEND                     
               conditional sequence.  These conditional words operated
               like:   
                       IF ... ELSE ... THEN          
               except that they cannot be nested, and are to be used only
               during interpretation.  In conjunction with the words [ and
               ] the words [ and ] they may be used within a colon
               definition to control compilation, although they are not to
               be compiled.

          INDEX        u1 u2 --                      M                    
               Print the first line of each screen over the range {u1..u2}.
               This displays the first line of each screen of source text,
               which conventionally contains a title.

          LAST         -- addr                       U                    
               A variable containing the address of the beginning of the
               last dictionary entry made, which may not yet be a complete
               or valid entry.

          LINE         +n -- addr                    M                    
               addr is the address of the beginning of line +n for the
               screen whose number is contained in SCR .  The range of +n
               is {0..15}.

          LINELOAD     +n u --                                 "line-load"
               Begin interpretation at line +n of screen u.








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          B.  UNCONTROLLED REFERENCE WORDS


          LOADS        u --                          M                    
               A defining word executed in the form: 
                       u LOADS <name>                
               When <name> is subsequently executed, block u will be
               loaded.

          MAP0         -- addr                                  "map-zero"
               A variable pointing to the first location in the tape map.

          MASK         n -- 16b                      
               16b is a mask of n most-significant bits if n is positive,
               or n least-significant bits if n is negative.

          MOVE         addr1 addr2 u --              
               The u bytes at address addr1 are moved to address addr2.
               The data are moved such that the u bytes remaining at
               address addr2 are the same data as was originally at address
               addr1.  If u is zero nothing is moved.

          MS           +n --                         M               "m-s"
               Delay for approximately +n milliseconds.

          NAND         16b1 16b2 -- 16b3             
               16b3 is the one's complement of the logical AND of 16b1 with
               16b2.

          NOR          16b1 16b2 -- 16b3             
               16b3 is the one's complement of the logical OR of 16b1 with
               16b2.

          NUMBER       addr -- d                     
               Convert the count and character string at addr, to a signed
               32-bit integer, using the value of BASE .  If numeric
               conversion is not possible, an error condition exists.  The
               string may contain a preceding minus sign.

          O.           u --                          M             "o-dot"
               Print u in octal format with one trailing blank.  The value
               in BASE is unaffected.

          OTHERWISE    --                            Interpret only       
               An interpreter-level conditional word.  See:  IFTRUE

          PAGE         --                            M                    
               Clear the terminal screen or perform a form-feed action
               suitable to the output device currently active.

          READ-MAP     --                            M          "read-map"
               Read to the next file mark on tape constructing a
               correspondence table in memory (the map) relating physical
               block position to logical block number.  The tape should
               normally be rewound to its load point before executing READ-
               MAP .




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          B.  UNCONTROLLED REFERENCE WORDS


          REMEMBER     --                            M                    
               A defining word executed in the form: 
                       REMEMBER <name>               
               Defines a word which, when executed, will cause <name> and
               all subsequently defined words to be deleted from the
               dictionary.  <name> may be compiled into and executed from a
               colon definition.  The sequence       
                       DISCARD REMEMBER DISCARD      
               provides a standardized preface to any group of transient
               word definitions.

          REWIND       --                            M                    
               Rewind the tape to its load point, setting CUR equal to one.

          ROTATE       16b1 n -- 16b2                
               Rotate 16b1 left n bits if n is positive, right n bits if n
               is negative.  Bits shifted out of one end of the cell are
               shifted back in at the opposite end.

          S0           -- addr                       U            "s-zero"
               A variable containing the address of the bottom of the
               stack.

          SET          16b addr --                   M                    
               A defining word executed in the form: 
                       16b addr SET <name>           
               Defines a word <name> which, when executed, will cause the
               value 16b to be stored at addr.

          SHIFT        16b1 n -- 16b2                
               Logical shift 16b1 left n bits if n is positive, right n
               bits if n is negative.  Zeros are shifted into vacated bit
               positions.

          TEXT         char --                       M                    
               Accept characters from the input stream, as for WORD , into
               PAD , blank-filling the remainder of PAD to 84 characters.

          USER         +n --                         M                    
               A defining word executed in the form: 
                       +n USER <name>                
               which creates a user variable <name>.  +n is the offset
               within the user area where the value for <name> is stored.
               Execution of <name> leaves its absolute user area storage
               address.

          WORDS        --                            M                    
               List the word names in the first vocabulary of the currently
               active search order.








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          B.  UNCONTROLLED REFERENCE WORDS


          \LOOP        +n --                         C,I       "down-loop"
                       sys --   (compiling)          
               A do-loop terminating word.  The loop index is decremented
               by the positive value +n.  If the unsigned magnitude of the
               resultant index is less than or equal to the limit, then the
               loop is terminated, otherwise execution returns to the
               corresponding DO .  The comparison is unsigned.  sys is
               balanced with its corresponding DO .  See:  DO

















































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