IIRC, the one-liner here [assuming you disabled the default "" operator] would be: Return Area( Distance'Base'(Left * Right) ); The apostrophe at the inne

IIRC, the one-liner here [assuming you disabled the default "" operator] would be: Return Area( Distance'Base'(Left * Right) ); The apostrophe at the inner portion is 'qualification', a method for directing the compiler that the enclosed value is supposed to be a particular subtype. (Typically used to resolve ambiguities.)