if(attrOutput==null) return tagLibTag;
Expression expr = CastBoolean.toExprBoolean(attrOutput.getValue());
if(!(expr instanceof LitBoolean))
throw new AttributeEvaluatorException("Attribute output of the Tag Function, must be a literal boolean value (true or false)");
boolean output = ((LitBoolean)expr).getBooleanValue();
if(output)
tagLibTag.setParseBody(true);
return tagLibTag;