#!/usr/local/bin/rune -x
#
#	Demonstrate the use of lvalue scope.  lvalue scope may be applied
#	to individual procedural arguments or to the return value.  It
#	causes the caller to pass the object by reference instead of by
#	value, allowing the procedure to modify the contents of the
#	object.
#
#	This feature is most often used when implementing operators that
#	require lvalues, such as "++" and "&=", but it can be used to
#	great effect with normal procedures as well.

import "sys";
import <stdio>;

class Fubar {
	int x;
	int y;
	heap lvalue int z;
	Fubar *link;

	method void
	test1()
	{
		this.x = 1;
	}

	method Fubar *
	test2()
	{
		return(&this);
	}

	method int
	test3()
	{
		return this.test4() + 1;
	}

	method int
	test4()
	{
		return this.y + 2;
	}
}

Fubar *g;
Fubar gg;

int
main(int ac, char **av)
{
	unlocked Fubar *a;
	Fubar **aa;
	Fubar *b;
	Fubar c;
	int x;
	(Fubar *xx, Fubar *yy) cc;
	unlocked int *xp;
	int **xpp;

	cc.xx = a;
	cc.yy = a;

	a = b;
	g = &gg;

	a.new();
	aa = &a;
	(*aa).new();
	a->x = 1;
	a->x = 2;
	a->x = 3;
	a->test1();
	b = a->test2();
	b = g->test2();
	xp = &x;
	xpp = &xp;
	*xpp = xp;	# clearing *xpp (i.e. contents of xp) before assignment XXX 
	*xpp = xp;
	**xpp = 45;
	**xpp = 46;
	**xpp = 47;

	b.new();
	b->x = 4;
	b->x = 5;
	b->x = 6;

	a->test3();

	b->link.new();

#	if (a->y < b->y)
#		x = 7;
#	else
#		x = 8;

#	if (c.z < c.z)
#		x = 9;
#	else
#		x = 10;

}

int *
xfubar(int *z)
{
	return z;
}