bean and property atrributes should be optional if value is provided

[ghost]

On a few occasions I've wanted to use f:display to render a value which is not a bean property. Here's a contrived example

<f:with bean="cb">
    <f:display value="${cb.calc()}" id="calc"/>
</f:with>

But the invocation of f:display without a property attribute causes an exception. I don't see why I should need to provide either a property or bean attribute when I'm specifying the field value like this?

[snimavat]

@domurtag @sbglasius ,

For this enhancement, How the display templates will be picked up, as property is not specified ? -- based on the type of value ? (obviously based on template resolution order)