Invalid Conditional Value
Control statements such as IF, FOR and WHILE require specific types for their condition.
If, While
IF and WHILE statements require an expression which yields a boolean, any other type is invalid and will trigger an
error.
For
FOR statements require four conditional values: a counter, a start value, an end value and a step value. All
of these need to be integers and share the same type.
FOR start := counter TO end BY step DO
// ...
END_FOR