replace_node
  
  Description:
  public void replace_node (
int pos, 
PathItem node)
  
 
  
    Replaces the exiting node at position pos in this.
    Parameters:
    
      
        | this | 
        
           a Path 
         | 
      
      
        | pos | 
        
           the position we want the new node to have. 
         | 
      
      
        | node | 
        
           pointer to a structure describing the GeglPathItem we want to store. 
         |