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Re: Revision of SRFI 76 available - questions and comments



Andre van Tonder <andre@xxxxxxxxxxxxxxxxxxx> writes:

>  Some miscellaneous issues: 
>   
>  > - I've changed the syntax of the OPAQUE and SEALED clauses to carry a
>  >   boolean operand.
>  
>  I notice this operand is evaluated at runtime.  I am not too familiar 
>  with the issues involved, but I suspect these attributes may 
>  be useful for compile-time analysis of allocation and optimization
>  strategies, which may become more difficult with this choice. 

Yes; I'll restrict the operands to #t and #f literally.

>  > - I've changed the semantics of field-id to always be local to the
>  >   specified rtd, rather than global.  This makes it easier to later
>  >   extend the abstractions to multiple inheritance, should anyone ever
>  >   want to do so, and leaves less room for ambiguity.
>  
>  I cannot find where this explained in the document.

It's in the specification of RECORD-ACCESSOR, specifically the
sentences:

>> Note that it is an error even if the procedure's argument is of a
>> parent type from which the selected field was inherited.

>> [...]

>> If it is a symbol s, the field named s from the fields argument to
>> make-record-type-descriptor is selected.

If you have suggestions on making it clearer, I'd be more than happy
to incorporate them.

>  > 
>  > - The field names passed to MAKE-RECORD-TYPE-DESCRIPTOR are now
>  >   required to be distinct.
>  
>  I think the sentence beginning with "If more than one field has the given name"
>  in the document is in conflict with this statement.

Well, not in conflict, but certainly nonsensical and confusing.  I'll
remove the sentence.
  
>  Also, I cannot figure out from the document if parent fields may be 
>  repeated in a child.

They may be.  I'll clarify.

>  Finally, I think an specification is still missing for the visibility 
>  of the various defined bindings in the various 'expression's 
>  occurring in the syntactic layer.  

Yes.  More thinking needs to be done here, but I'm glad we both seem
to agree there's been progress.

-- 
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla