Recurring information pattern: generate layers of information andthen me

["Costello, Roger L." <costello@mitre.org>]

Hi Folks,

A friend of mine takes photos of small things such as small insects (I believe it's called macrophotography). His photos are awesome -- every detail is visible and it is very 3-D. He informs me that he takes multiple photos. That is, he takes layers of photos and then merges them together.

It occurred to me that generating layers of information and then merging them is a recurring information pattern.

Consider: in XML Schema one can create a data type that restricts another data type. For example, BostonAreaSurfaceElevation restricts EarthSurfaceElevation:

    <simpleType name="EarthSurfaceElevation">
        <restriction base="integer">
            <minInclusive value="-1290" />
            <maxInclusive value="29035" />
        </restriction>
    </simpleType>
    
    <simpleType name="BostonAreaSurfaceElevation">
        <restriction base=" EarthSurfaceElevation ">
            <minInclusive value="0" />
            <maxInclusive value="120" />
        </restriction>
    </simpleType>

One can think of that as two layers of information. After merging the two layers one understands the total set of constraints on an element declared to be of type BostonAreaSurfaceElevation.

Unfortunately, merging layers of simpleType elements is not a trivial processing task. Perhaps simpleType elements could be restructured in a way that makes merging them trivial? Any ideas?

Would you provide other examples of where layers of information are generated and then merged?

It would be powerful if we could identify a "layering format" that could be applied to any kind of information and which lends itself to a trivial merge operation.

Recap:

1. Let's identify a generic layering format.

2. Let's identify a trivial merge operation for merging layers of information.

Thoughts?

/Roger