to_s()
  public
  
    
    
Returns a string representing obj. The default to_s prints the object’s class and an encoding of the object id. As a special case, the top-level object that
is the initial execution context of Ruby programs returns “main”.
   
  
    Show source    
    
      VALUE
rb_any_to_s(VALUE obj)
{
    VALUE str;
    VALUE cname = rb_class_name(CLASS_OF(obj));
    str = rb_sprintf("#<%"PRIsVALUE":%p>", cname, (void*)obj);
    OBJ_INFECT(str, obj);
    return str;
}