for (int p=0; p<actualParams.length; p++) {
WithParam wp = actualParams[p];
int id = wp.getParameterId();
LocalParam lp = template.getLocalParam(id);
if (lp != null) {
SequenceType req = lp.getRequiredType();
RoleLocator role = new RoleLocator(RoleLocator.PARAM, wp.getVariableQName().getDisplayName(), p);
Expression select = TypeChecker.staticTypeCheck(
wp.getSelectExpression(), req, backwards, role, visitor);
wp.setSelectExpression(select);
wp.setTypeChecked(true);