tree = parse("${ns:f2(21,21)}");
assertEquals(foobar(21,21), getNode(tree).eval(tree.bind(context.getFunctionMapper(), null), null));
tree = parse("${g0()}");
assertEquals(foo(), getNode(tree).eval(tree.bind(context.getFunctionMapper(), null), null));
tree = parse("${g1(42)}");
assertEquals(bar(42), getNode(tree).eval(tree.bind(context.getFunctionMapper(), null), null));
tree = parse("${g2(21,21)}");