ISO Pascal reference manual

patterns (integer values); if the extended form of the compiler is being used,
the bit-vector operators le and `1' may be used.
PROGRAM fail;
VAR x : integer;
BEGIN
END.
b : boolean;
IF x AND b THEN writeln('hello'); [x isn't boolean}
*ERROR 35 -- the operand to the right of must give
a boolean value
The reserved words AND, OR and NOT must be followed by a boolean
operand. In particular they may not be used to form conjunctions,
disjunctions or inversions of bit patterns (integer values); if the extended
form of the compiler is being used the bit-vector operators le, `1' and `~'
may be used.
PROGRAM fail;
VAR x : integer;
BEGIN
END.
b : boolean;
IF b AND x THEN writeln('hello');
*ERROR 36 -- this integer value is too large .
This message is issued when the compiler detects that the function SQR has
as its parameter an integer constant which is larger than the square root of
the largest possible integer. Attempting to square this value would lead to
an arithmetic fault at run-time.
PROGRAM fail(output);
BEGIN
END.
writeln(SQR(123456)); (123456 is too big for SQR}
56 Pascal Issue 1