sometimes the following might cause a problem due to the compiler not being
sure if a Char or a String is being referred to:
const
SNum = '1';
so, to avoid possible run-time errors with constants where you need to be sure
that they are of a certain type (eg if later doing a StrComp or similar) then
'typecast' the constant, like this:
const
SNum = String('1');
OR, say:
const INCHES_PER_MILLIMETER: Real = 0.04;