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Resumption of execution is not permitted with a CaNT command. Variables within the statement or
program retain their values so they may be scrutinized to determine a cause of error, if
necessary. GOSUB and FOR entries on the stack at the time of error are cleared so resumption of
execution is not possible by RETURN or NEXT.
POSSIBLE BASIC MESSAGES AND MEANINGS
Bad subscript- An attempt was made to reference a matrix element which is outside the dimensions of
the matrix. This may happen by specifying the wrong number of dimensions or a subscript larger than
specified in the original dimension.
DIM A(2,2)
A(1,1,1)~2
?BAD SUBSCRIPT ERROR
READY,
A(10,10)=2
?BAD SUBSCRIPT ERROR
READY,
Can't continue·Program execution cannot be resumed via a CONT command in four cases:
1) no program exists.
2) a new line was just typed in.
3) the program has not recently been run.
4) an error just ocurred.
10A$='HELLO'
CONT
'CAN'T CONTINUE ERROR'
READY,
Dlvisic;m by zero-Zero as a divisor would result in numeric overflow--thus it is not allowed. When this
message appears, it is most expedient to list the statement and look for division operators.
?DIVISION BY ZERO ERROR IN 10
LIST 10
lOA
=
BIC
?C
o
Formula too complex--This message concerns only string expressions when BASIC runS out of string
temporary pointers to keep track of substrings in evaluating a string expression.
?FORMULA TOO COMPLEX ERROR
READY,
Break the string expression into tYio smaller parts to cure the problem.
Illegal direct··A single 80 column buffer area is used by BASIC to process incoming ch aracters. This same
buffer is used to hold a statement that is being interpreted in direct mode. INPUT will not work because
incoming characters would overwrite the variable list following INPUT to be processed.
DEF cannot be used in direct mode for a different but similar reason. The name of a funcrlon is stored in
the BASIC variable area with pointers to the string of caharacters which define the function. Since the
function exists only in the input buffer, it would be wiped out the first time a new command is typed-in.
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