Re: SpecGL: rewrite of Strict Conformance

The major dilemma we had was as follows:
A product could vary along some Dimensions of Variability, notably
discretionary choices, but not implement any extensions. Is this
"strict conformance"?

Lynne proposes:
>8.  Insert the following as the 3rd paragraph in Guideline 9
>Disallowing extensions for any part of the specification is called strict
>conformance.  [te paragraph from G3]  Strict conformance is defined as
>conformance of an implementation that employs only the requirements and/or
>functionality defined in the specification and no more (e.g., no
>extensions to the specification are implemented).  No discretion is
>granted to implementers, and any requirements for handling deprecated
>features must be followed.

As a way to confirm your intent, I deduce that the "strict conformance"
definition in GL 9 actually relates to several DoV as enumerated below.
Strict Conformance means *all* of the following are true:
(GL 6) there are no levels (unclear)
(GL 7) no variation is allowed in treatment of deprecated features
(GL 8) no discretionary items exist in the spec
(GL 9) no extensions are allowed

On the other hand, the strict conformance policy can apply only to some
of the product classes (GL 2), some profiles (GL 4), or some modules
(GL 5). If true, this validates the numerical order of the guidelines
going from general to specific. (It still would if GL 6 "crossed the
line" and Strict Conformance applied on a per-level basis.)

I would like the wording to be explicit about profiles, modules, and
levels. I think that Strict Conformance should mean that there are no
levels, as part of the goal to make it a useful term.

Notice that the interaction between the definition and deprecation is
slightly different than the others. Deprecation is compatible with
Strict Conformance, as long as you don't have discretionary choices (GL 8)
regarding the deprecated features. Fine point: if all implementations
must consume deprecated content and treat it in some specified way (e.g.,
must ignore it), does the discretionary choice of whether to warn the
user about deprecated input violate Strict Conformance? If so, we are
being really strict, because issuance of warnings might be a minor
secondary effect to most (but not all) implementors.
.................David Marston

Received on Thursday, 16 January 2003 16:21:58 UTC