F Finalization

[CHANGED:] This appendix lists the main points that have been addressed since version 0.99 of this document appeared. For further details of the discussions, see the mailing list archives.

Views:

Implicit views have been removed, since the semantics was too complicated (at least for implicit generic views). The inclusion of so-called `principal sorts' (to help in determining default fitting views) was reconsidered, but finally rejected. A symbol map may be completed to a (unique) signature morphism from the parameter to the argument specification, which should often allow simple instantiations to be expressed sufficiently concisely.

Architectural specifications:

Grouping braces for architectual specifications and unit terms have been introduced, to make the concrete syntax less ambiguous.

Specification libraries:

The details of version control have been considered in greater depth, as will be reported in a forthcoming study note.

Semantics:

The checking that the proposed changes to CASL in version 1.0 can be given a sensible semantics is almost complete, and the formal semantic description given for version 0.97 of CASL [CoF97f] is being updated (effectively) to version 1.0.

Parsing:

The various parsers that have already been implemented for basic and structured specifications still need to be completed and validated. Until then, the details of the input syntax are regarded as subject to minor changes. A prototype implementation of the grouping analysis of mixfix terms and formulae (which is dependent on the declared identifiers) has been made.

Formatting:

The LaTeX and HTML display of CASL specifications has been optimized, and is to be released as a package, along with the updated versions of the CoFIdoc package and CoFI Bibiliography that were used for producing this document.

Annotations:

The form of parsing annotations and their rôle in parsing and formatting still needs to be clarified. The set of semantic annotations to be provided by CASL needs to be decided, together with their syntax; a proposal for some standard tool annotations for syntactic and static semantic analysis has been made in Tools Note T-6 [Mos98].