/*
 * masarl@nifty.com
 * http://homepage3.nifty.com/masarl/article/js-oop.html#oop-js
 */

function copy_undef_properties(src, dest)
{
    for (var prop in src) {
        if (typeof(dest[prop]) == "undefined") { 
            dest[prop] = src[prop];
        }
    }
}

function inherit(subClass, superClass) 
{
    copy_undef_properties(superClass.prototype, subClass.prototype);
}

function dynamic_inherit(instance, dynamicClass, 
                         arg1, arg2, arg3, arg4, arg5,
                         arg6, arg7, arg8, arg9, arg10)
{
    copy_undef_properties(dynamicClass.prototype, instance);
    instance.temp = dynamicClass;
    instance.temp(arg1, arg2, arg3, arg4, arg5, 
                  arg6, arg7, arg8, arg9, arg10); 
    return instance;
}

function copy_properties(src, dest)
{
    for (var prop in src) {
        dest[prop] = src[prop];
    }
}

function force_inherit(subClass, superClass) 
{
    copy_properties(superClass.prototype, subClass.prototype);
}

function force_dynamic_inherit(instance, dynamicClass, 
                               arg1, arg2, arg3, arg4, arg5,
                               arg6, arg7, arg8, arg9, arg10)
{
    copy_properties(dynamicClass.prototype, instance);
    instance.temp = dynamicClass;
    instance.temp(arg1, arg2, arg3, arg4, arg5, 
                  arg6, arg7, arg8, arg9, arg10); 
    return instance;
}