moving a rectangle with a mouse

[edexter]

uses phxInput,
     phxCanvas;

var Input:  TPHXInput; 
var Canvas: TPHXCanvas;

begin

Input:= TPHXInput.Create; 

Canvas:= TPHXCanvas.Create; 
while true do begin;

  Canvas.Rectangle(Input.Mouse.X - 10, Input.Mouse.Y - 10, Mouse.Input.Mouse.X + 10, Input.Mouse.Y + 10); 
end; 

end.

I am getting mouse the mouse is an unidentified var... will I be able to turn this into a custom slider.[/code]