Schema element "`b:constant`"

The payload of Constant describing Unit.

Definitions

<element name="constant" type="b:Constant_"
  substitutionGroup="b:native" />

<complexType name="Constant_">
  <complexContent>
    <extension base="b:Native">
      <sequence>
        <element ref="b:preview" [0..1] />
      </sequence>
    </extension>
  </complexContent>
</complexType>

Description

Constants are basically names which are unique, as 'enum'-types in many languages show. But they also have implications. The Unit which MAY be linked to the Constant supports life-cycle management over this constant and MAY contain documentation. But also: it can explain the constant to client and server.

element `preview`

A Constant (b:Constant is a b:UnitRef) points to a fact within a group of facts. However, to be useable, that fact may need more information: additional details to the constant to reduce exploding dimensions of possible parameters.

For instance, when the Constant is named ms:Signature/SHA256, then it is useful to know that the algorithm is SHA and the version 256. Either the backend must interpret the UnitID SHA256, or this is resolved via parameters, typically "algorithm=SHA, bits=256".

Discussion

Why parameters and not cleanly spec'd

Purist would certainly prefer to have clean schemas over a list of keu-value parameters, but it is simply too much work with little to add.

mark@overmeer.net Web-pages generated on 2023-12-19