Re: [fpc-pascal] Case in Record

[Vincent Snijders]

Jürgen Hestermann schreef:
Therefore, there is absolutly no difference between
TFigure = record
          X : TShapeList;
          case TShapeList of
             Rectangle: (Height, Width: Real);
             Triangle: (Side1, Side2, Angle: Real);
             Circle: (Radius: Real);
             Ellipse, Other: ();
             end;

and

TFigure = record
          case X : TShapeList of
             Rectangle: (Height, Width: Real);
             Triangle: (Side1, Side2, Angle: Real);
             Circle: (Radius: Real);
             Ellipse, Other: ();
             end;

It ends up in the same record and also the programmer does not see any 
difference. He can store whatever he wants in X in both cases. It has no 
influences on the variants.

IIRC, there is a difference. With the second declaration the compiler can add a 
run-time check that the correct memebrs are accessed based on the value of X.

Unfortunately, I cannot find the compiler switch.

Vincent
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