New words demonstration

% by Kevin Doyle
% For more details see F.NewWord
% Published by AMPLINEX May 1990

% Can be *EXECed into AMPLE

% Define new words as GVAR

"findword" [GVAR]
"wordname" [GVAR]
"nextword" [GVAR]
"wordshow" [GVAR]

% Set up the above words with the
% values required

15 findword #! &2E findword 1 #- #B!
15 wordname #! &59 wordname 1 #- #B!
15 nextword #! &73 nextword 1 #- #B!
15 wordshow #! &B8 wordshow 1 #- #B!

% Use new words in utility

"FREE" [
OFF            % Set start value of 0
               % for nextword
REP(           % Begin main loop: this
               % loop gets the token
               % for each user word.
               % This token will be
               % the object searched
               % for in each user word
               % in the sub-loop below
 6 nextword    % Get address of first
               % (or next) user word
)UNTIL(        % Continue whilst more
               % words

 OFF #212      % Put OFF flag on stack
               % and copy object word
               % address to top. OFF
               % flag is used to
               % indicate the initial
               % state - i.e. that no
               % occurrence of the
               % object token has been
               % found
 4 #+          % Add 4 to address to
               % point to word name
               % length byte
 #11           % Duplicate address

 #B?           % Read word length byte
 15 AND        % Remove top bit (&80)
               % to give word length
 #+            % Add word length to
               % address to point to
               % end of word name
 1 #+          % Add 1 to address to
               % point to word token
 #?            % Read word token bytes
               % (i.e. token + &00)
 #B12          % Reverse bytes to give
               % &00 + token, the form
               % of the token used in
               % word definitions.
               % This gives the object
               % token to be searched
               % for in the next loop

 OFF           % Set start value of 0
               % for nextword
 REP(          % Begin sub-loop
  6 nextword   % Get address of first
               % (or next) user word
 )UNTIL(       % Continue whilst more
               % words
  #2121        % Duplicate top two
               % items on the stack
               % (i.e. the object word
               % token and the target
               % word address)
  4 #+         % Add 4 to address to
               % point to word name
               % length byte
  #11          % Duplicate address

  #B?          % Read word length byte
  15 AND       % Remove top bit (&80)
               % to give word length
  #+           % Add word length to
               % address to point to
               % end of word name
  3 #+         % Add 3 to address to
               % point to start of
               % target word
               % definition
  findword     % Find next occurrence
               % of object token in
               % target word. Returns
               % address ON if found;
               % OFF if not found
  #11          % Duplicate find flag

  IF(          % If found:
   #12 #2      % Delete found address
               % from stack
   FRAME       % Set frame pointer to
               % top of stack
   FRAME?      % Read frame pointer
   ON          % Set fourth element
   4 FVAR      % on stack to ON to
   #!          % indicate that the
               % object token has
               % been found in the
               % target word. This
               % will replace the OFF
               % flag put on the
               % stack near the start
    FRAME!     % Write frame pointer
  )IF          % End of conditional

 )UNTIL(       % Repeat above until
               % object found in
               % target word
 )REP          % End of sub-loop

 #2            % Delete target address
               % from stack
 #2            % Delete object token
               % from stack
 NOT           % Reverse flag - i.e.
               % OFF (not found) => ON

 IF(           % If object token not
               % found in any target
               % word
  #11          % Duplicate address of
               % object word
  4 #+         % Add 4 to address to
               % point to word name
               % length byte
  wordname     % Return string
               % containing word name
  wordshow     % Pad out to fixed
               % length and print
 )IF           % End of conditional
)REP           % End of main loop
#2             % Delete last address
]

% Type FREE to use the utility

---

Published in AMPLINEX 017, May 1990