

		ABSTRACT FOR RENUMB.BAS
		=======================

	RENUMB WILL RE-NUMBER THE LINES OF ANY RT-11 SINGLE USER BASIC
PROGRAM.  VARIOUS ERROR CONDITIONS ARE DETECTED AND FLAGGED;  THE PROGRAM
CAN THEREFORE BE USED FOR DIAGNOSING SIMPLE PROGRAM ERRORS.





		WRITE-UP FOR RENUMB.BAS
		=======================

	RENUMB.BAS,  WRITTEN IN SINGLE USER RT-11 BASIC,  IS A PROGRAM
TO RE-NUMBER THE LINES OF ANY PROGRAM WRITTEN IN THE SAME LANGUAGE.  THE
USER MUST SPECIFY THE NAME OF THE FILE TO BE RE-NUMBERED,  THE NAME OF
THE NEW FILE TO STORE THE RE-NUMBERED PROGRAM,  THE FIRST LINE NUMBER
OF THE RE-NUMBERED PROGRAM AND THE STEP SIZE BETWEEN LINES.  ANY LEGAL
RT-11 FILE NAMES ARE PERMISSIBLE;  THE DEFAULT DEVICE (DK:) AND THE FILE
EXTENSION .BAS ARE ASSUMED IF NOT SPECIFIED.  THE OLD AND NEW FILE NAMES
MAY BE THE SAME.  A COPY OF THE ORIGINAL PROGRAM IS STORED IN THE FILE
DK:RENUMB.COP;  THIS SAFEGUARDS AGAINST UNINTENTIONAL INTERRUPTIONS OF
THE POGRAM WHILE RE-NUMBERING IS IN PROGRESS.  RENUMB CHANGES ALL LINE
NUMBER REFERENCES EXCEPT THOSE WITHIN REM STATEMENTS.

THE FOLLOWING ERROR CONDITIONS ARE DETECTED:

	1.  REFERENCE TO AN UNDEFINED LINE NUMBER.  THE OFFENDING LINE
	    NUMBER IS REPLACED BY *???*, AN ERROR MESSAGE IS TYPED AND
	    RE-NUMBERING CONTINUES.
	2.  LINE NUMBER WITH NO STATEMENT.  A WARNING MESSAGE IS TYPED
	    AND RE-NUMBERING CONTINUES.
	3.  LINE LONGER THAN 72 CHARACTERS (AFTER RE-NUMBERING).  THE
	    LINE IS TRUNCATED TO 72 CHARACTERS, AN ERROR MESSAGE TYPED
	    AND RE-NUMBERING CONTINUES.
	4.  LAST LINE NUMBER IS LARGER THAN THE LEGAL BASIC MAXIMUM.
	    A WARNING MESSAGE IS TYPED.
	5.  PROGRAM IS TOO LONG TO BE RE-NUMBERED.  RUN IS ABORTED AND
	    AN ERROR MESSAGE TYPED;  SEE PROGRAM LISTING TO ALTER MAXIMUM
	    LENGTH.  NOTE:  IF OLD AND NEW PROGRAM NAMES WERE THE SAME,
	    THE FILE WILL HAVE BEEN CORRUPTED AND THE ORIGINAL PROGRAM
	    WILL BE STORED IN RENUMB.COP.
	6.  LINE NUMBERS IN ORIGINAL PROGRAM NOT IN ASCENDING ORDER.
	    RUN IS ABORTED AND AN ERROR MESSAGE PRINTED.  SEE NOTE FOR
	    ERROR CONDITION 5 ABOVE.



		RUNNING RENUMB
		==============

	RENUMB IS RUN AS A STANDARD BASIC PROGRAM UNDER ANY VERSION OF
BASIC WITH STRING SUPPORT.
E.G:-

.R BASIC

BASIC V01-05.2
*

READY

OLD
OLD FILE NAME--RENUMB

READY

RUN


NOTES:	1.  RENUMB EXPECTS ALL LINE NUMBER REFERENCES TO BE DELIMITED
=====	    BY SPACES.  FOR EXAMPLE GO TO100 WILL NOT BE DETECTED AS
	    A LINE REFERENCE.  THIS PROBLEM CAN BE OVERCOME IF THE
	    PROGRAM IS STORED (OR REPLACED) FROM THE BASIC COMMAND LEVEL
	    BEFORE RUNNING RENUMB, AS ANY MISSING SPACES WILL BE INSERTED
	    BY BASIC.
	2.  IF THE LAST LINE OF THE ORIGINAL PROGRAM IS NOT TERMINATED
	    WITH A <CR>,  BASIC WILL TYPE ?OOD AND THE RUN WILL BE
	    ABORTED.  THE ORIGINAL PROGRAM WILL BE SAVED IN RENUMB.COP.



					NICK HAMMOND,
					NEUROPSYCHOLOGY RESEARCH UNIT,
					FRIERN HOSPITAL,
					FRIERN BARNET RD.,
					LONDON N11 3BP,
					ENGLAND

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