PortValue class that have a pair of a deriving class of
Port and a deriving class of object. The following
codes are parts of PortValue.cs.
class PortValue {
public:
public Port port; //-- either an output or an input port
public object value; // deriving class from the Object class
public PortValue(Port prt){...}
public PortValue(Port prt, object v) {...}
public void Set(Port prt){...}
public void Set(Port prt, object v){...}
public override string ToString(){...}
};
Two constructors and two Set functions are available whose
arguments can be Port p which means value v=null, or
a pair of (Port p and object
v). The function ToString() returns the string concatenating
of port and value (if value is not
null) by using a delimiter `:' character.