Expression content = prepareExpressionAsParameterValue(contentParam,
apply(call.getContent()));
boolean contentIgnorable = content.alwaysOnlyWhitespace();
if (contentParam == null) {
if (!contentIgnorable) {
alertSink.add(new BadNodePlacementError(content, call));
}
} else {
String paramName = contentParam.getPrimaryName();
if (!contentIgnorable && params.containsKey(paramName)) {
alertSink.add(new MultiValueAttributeError(call, params.get(paramName)));