with text_io;
procedure top is
 
package IIO is new Text_IO.Integer_io(integer); --need integer output

function viper(Left:in INTEGER; Right:in INTEGER:=1) return INTEGER;
 
function "+"(Left:in INTEGER; Right:in INTEGER) return integer renames viper;
 
function viper(Left:in INTEGER; Right:in INTEGER:=1) return INTEGER is
begin
	return STANDARD."+"(Left, Right);
end viper;
 
begin
	iio.put(viper(1,2));
	text_io.new_line;
	IIO.PUT(viper(2));
	text_io.new_line;
	iio.put(1+2);
	text_io.new_line;
END;