Nim boilerplate

[LokeX]

Hey, thanks mate!

I can't get the:
    
    
    a.kind is Circle
    
    
    Run

to work.

But i got this:
    
    
    type
      ShapeKind = enum Circle,Rectangle
      ShapeProps = tuple[shape:string,area,perimeter:float]
      CircleShape = concept a
        a.r
        proc buildCircleProps(a:CircleShape):ShapeProps
      RectangleShape = concept a
        a.w
        a.h
        proc buildRectangleProps(a:RectangleShape):ShapeProps
    
    
    Run

And it works!

You can use:
    
    
    proc buildRectangleProps(a:Shape):ShapeProps
    
    
    Run

as you did, or:
    
    
    proc buildRectangleProps(a:RectangleShape):ShapeProps
    
    
    Run

either way it works...

I had tried variations on that, but apparently never happened on the complete 
deal - I'm such an idiot at times...

Thanks again for you generous help, and for the Iface tip. Though I'd rather 
use concepts, it's nice to know it's there.