final Constraint constr = _auxinf != null ? _auxinf.constr: null;
if (constr instanceof CustomConstraint) { //client ignored if custom
renderer.render("constraint", "[c"); //implies validated at server
constrDone = true;
} else if (constr instanceof ClientConstraint) {
final ClientConstraint cc = (ClientConstraint)constr;
try {
render(renderer, "z$pk", cc.getClientPackages());
final String js = cc.getClientConstraint();
if (js != null) {
final char c = js.length() > 0 ? js.charAt(0): (char)0;
if (c != '\'' && c != '"') {
renderer.renderDirectly("z$al",
"{constraint:function(){\nreturn "+js+";}}");