@Override
    public DataType setOutputType(DataType outputType, TypeContext context) {
        super.setOutputType(outputType, context);

        if (defaultExp != null)
            setOutputType(outputType, defaultExp, context);
        for (Expression expression : cases.values())
            setOutputType(outputType, expression, context);
        return DataType.STRING;
    }
The default expression, or null if none
indexinglanguage/src/main/java/com/yahoo/vespa/indexinglanguage/expressions/SwitchExpression.java