ISO Pascal reference manual

*ERROR 91 -- this is not a valid case selector
Appendix A
This message is issued when the extended forms of NEW or DISPOSE are
used and the extra parameters do not correspond to the variables in the
CASE parts of the record description.
PROGRAM fail;
BEGIN
END.
TYPE three = 1..3;
rec = RECORD CASE x:three of
END;
point =trec;
VAR thing : point;
1:(a : integer);
2:(b : real);
3:(c : char);
new(thing, 2); (2 is ok for x above(
new(thing, 4); (but 4 is not(
*ERROR 92 -- this statement threatens to alter the loop control
variable
The control variable of a FOR loop may not be used inside the body of the
loop in such a way as to threaten to alter it. This means that the variable
cannot appear to the left of : = , as a VAR parameter or as the control
variable of a nested FOR statement. Note that the error only indicates that
the variable is threatened; it is still an error even though the variable can
never actually be altered.
PROGRAM fail(input);
VAR j, k : integer;
BEGIN
END.
FOR j := 1 to 10 DO BEGIN
END;
read(k)
IF k = 0 THEN j := 10 (wrong}
Pascal Issue 1 77