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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