00001REM   TUT16
00100PRINT"IN THE PREVIOUS SESSION,YOU WERE ASKED TO PERFORM SOME OPERATIONS"
00110PRINT"ON A TEST PROGRAM.  HOPEFULLY, YOU ARE BECOMING MORE FAMILIAR"
00120PRINT"WITH THE CAPABILITIES FOR MODIFYING PROGRAMS."
00130PRINT
300 PRINT"SUPPOSE YOU EDIT A PROGRAM WHICH YOU HAVE PREVIOUSLY SAVED. WHICH"
310PRINT"OF THE FOLLOWING COMMANDS WOULD BE NECESSARY IF THE RESULTING"
320PRINT"PROGRAM WERE TO BE OF ANY USE TO YOU IN THE FUTURE."
00330PRINT
340PRINT"(1) NEW    (2) OLD    (3) SAVE    (4) REPLACE  ";
00350INPUTZ
00360PRINT
370 IF Z=4 THEN 400
00380PRINT"NO.  ";
00390GO TO 410
00400PRINT"RIGHT.  ";
00410PRINT"'SAVE' WILL STORE THE NEWLY INCREMENTED PROGRAM IN YOUR LIBRARY."
420PRINT"'REPLACE' IS DONE TO REPLACE A PROGRAM PREVIOUSLY SAVED WITH"
430PRINT"A NEW VERSION OF THAT PROGRAM."
00440PRINT
450PRINT"LET'S DISCUSS THE 'SAVE', 'UNSAVE', 'REPLACE', 'OLD', 'NEW', AND"
460PRINT"'RUN' COMMANDS IN MORE DETAIL."
461PRINT\PRINT"'NEW' IS USED TO TELL THE COMPUTER YOU ARE GOING TO ENTER":
	PRINT"A NEW PROGRAM FROM YOUR TERMINAL."
462PRINT\PRINT"'SAVE' IS USED TO STORE A PROGRAM IN YOUR PERSONAL LIBRARY ONCE":
	PRINT"YOU HAVE TYPED THAT PROGRAM INTO THE COMPUTER."
463PRINT:PRINT"'REPLACE' IS USED TO SAVE AN EDITED COPY OF A PREVIOUSLY SAVED ":
	PRINT"PROGRAM. THE NEW VERSION REPLACED THE OLD ONE."
464PRINT:PRINT"'OLD' RETRIEVES A PROGRAM FROM YOUR LIBRARY WHICH WAS PREVIOUSLY":
	PRINT"SAVED. THE PROGRAM IS AVAILABLE FOR LISTING, EDITING, OR RUNNING."
00470PRINT
475PRINT"'UNSAVE' IS USED TO DELETE A PROGRAM ALREADY SAVED IN YOUR LIBRARY.":
	PRINT"TYPE 'UNSAVE NAME' TO DELETE THE PROGRAM CALLED 'NAME'."
480PRINT:PRINT"'RUN NAME' IS EQUIVALENT TO USING 'OLD NAME' FOLLOWED BY A 'RUN'":
	PRINT"COMMAND."
485 PRINT
00520PRINT"HERE ARE 4 COMBINATIONS OF COMMANDS, PRODUCING DIFFERENT EFFECTS."
00530PRINT
00540PRINT"     1. TYPE 'UNSAVE' WHILE WORKING ON A 'NEW' PROGRAM."
550PRINT"     2. TYPE 'REPLACE' WHILE WORKING ON A 'NEW' PROGRAM."
00560PRINT"     3. TYPE 'UNSAVE' WHILE WORKING ON AN 'OLD' PROGRAM."
00570PRINT"     4. TYPE 'NEW' WHILE WORKING ON AN 'OLD' PROGRAM."
00580PRINT
00610PRINT
00620PRINT"WHICH ONE REMOVES THE PROGRAM FROM PERMANENT MEMORY (LIBRARY),"
00630PRINT"BUT LEAVES IT IN WORKING CORE. ";
00640INPUTZ
00650PRINT
00660IFZ=3THEN690
00670PRINT"NO, GUESS AGAIN  (YOUR ODDS HAVE IMPROVED). ";
00680GOTO640
00690PRINT"RIGHT.   WHICH ONE WOULD SEEM LIKE A MEANINGLESS OPERATION. ";
00700INPUTZ
00710IFZ=1THEN750
00730PRINT"ARE THEY ALL MEANINGLESS TO YOU?  GUESS AGAIN. ";
00740GOTO700
00750PRINT"VERY GOOD.  NOW, WHICH ONE COULD CONCEIVABLY REPLACE A "
00760PRINT"PREVIOUSLY SAVED PROGRAM WITH AN ALTOGETHER DIFFERENT PROGRAM.  ";
00770INPUTZ
00780PRINT
00790IFZ=2THEN830
00800PRINT"NO.  THIS REQUIRES AN EXPLANATION OF THE STORAGE (SAVE) PROCEDURE."
00820GOTO840
00830PRINT"SHEER GENIUS.  OR A VERY LUCKY GUESS."
840PRINT"WHEN YOU REQUEST A PROGRAM TO BE SAVED, A SEARCH IS FIRST MADE"
850PRINT"IN YOUR LIBRARY TO SEE IF THE REQUESTED NAME IS THE SAME AS AN"
860PRINT"EXISTING PROGRAM NAME. IF SO, AN ERROR MESSAGE IS PRINTED. YOU THEN"
870 PRINT"USE THE COMMAND 'REPLACE'. REMEMBER, YOU CAN EXAMINE THE LIST OF"
880PRINT"PROGRAM NAMES STORED IN YOUR LIBRARY BY TYPING 'CAT'."
01000PRINT
01010PRINT"I DIDN'T ASK YOU A QUESTION ABOUT NUMBER 4 ABOVE - TYPING 'NEW'"
01020PRINT"WHILE WORKING ON AN 'OLD' PROGRAM.  WILL THIS DESTROY A PROGRAM?"
1030 PRINT "(YES OR NO)";
1040INPUT Z$
01050PRINT
1060PRINT"IT WILL, BUT ONLY THE PROGRAM IN WORKING CORE IS DESTROYED. IF"
01070PRINT"YOU WANT THE CHANGES YOU MAY HAVE MADE INCORPORATED INTO THE"
1080PRINT"'OLD' PROGRAM, YOU NEED TO TYPE 'REPLACE' BEFORE TYPING 'NEW'."
01090PRINT
01100PRINT
1110PRINT"THERE ARE SEVERAL OTHER SYSTEM COMMANDS..."
1160PRINT"AMONG THOSE ARE THE CTRL/U AND RUBOUT KEYS, BOTH"
01210	PRINT"ON THE KEYBOARD. PERHAPS YOU HAVE USED ONE OR BOTH OF THESE IN"
01220PRINT"CASE YOU HAVEN'T, LET'S TRY THEM OUT.  THE RUB-OUT IS FOR ERASING"
01230PRINT"SINGLE CHARACTERS (INCLUDING SPACES) YOU HAVE TYPED.  FOR EXAMPLE"
01240PRINT"ENTER A SINGLE DIGIT ";
01250INPUTN
01260PRINT
01270PRINT"YOU TYPED IN THE NUMERAL  ";N;"THAT TIME.  NOW TYPE IN A NUMBER"
01280PRINT"HAVING FOUR OR FIVE DIGITS, AND FOLLOW IT IMMEDIATELY WITH TWO"
01290PRINT"RUB-OUTS FOLLOWED BY ONE OR TWO"
01291PRINT"OTHER DIGITS.  TRY IT.";
01300INPUTM
01310PRINT
01320PRINT"YOU TYPED IN THE NUMERAL  ";M;"THAT TIME.  SEE HOW IT WORKS?"
01330PRINT"A SINGLE RUB-OUT WOULD HAVE ERASED THE LAST DIGIT, THREE RUB-OUTS"
01340PRINT"THE LAST THREE DIGITS, AND SO ON.  THE OTHER EDIT COMMAND I"
1350PRINT"MENTIONED, 'CTRL/U', WILL DELETE AN ENTIRE LINE OR EVEN"
01360PRINT"COMMANDS, SUCH AS 'SAVE', IF IT IS USED PRIOR TO THE CARRIAGE"
01370PRINT"RETURN.  TRY IT WHEN YOU WANT TO CANCEL A LINE YOU HAVE TYPED."
1371 PRINT:PRINT"MOST RSTS COMMANDS ARE STRAIGHT-FORWARD AND SELF-EXPLANATORY"
1372 PRINT"OTHER COMMANDS ARE DESCRIBED IN THE RSTS SYSTEM USER'S GUIDE."
1373 PRINT"THERE IS A SUMMARY OF RSTS COMMANDS IN AN APPENDIX TO BOTH THE"
1374 PRINT"RSTS SYSTEM USER'S GUIDE AND THE BASIC-PLUS LANGUAGE MANUAL."
1375 PRINT"YOU MIGHT WANT TO SKIM THROUGH THEM AT THIS TIME.":PRINT
1380PRINT"RUN 'TUTR17'WHEN YOU'RE READY TO CONTINUE---SEE YOU THERE."
9999END