How to conditonally include elements in a list?

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2

By conditional adding empty lists:

    Canvas.shapes
        [ -- Settings
          Canvas.Settings.Line.lineWidth 5
        , Canvas.Settings.Line.lineCap Canvas.Settings.Line.RoundCap
        , Canvas.Settings.stroke Color.black
        ]
       ( [ -- Shapes
          path ( 2, 297 )
      ]
     ++ 
     if (model.turns > 10 )then
            -- Draw the stand.
            [ lineTo ( 297, 297 )
            , moveTo ( 13, 297 )
            , lineTo ( 13, 3 )
            , lineTo ( 150, 3 )
            , lineTo ( 150, 25 )
            ]
     else
         []
    ++ ...