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Re: [ddlm-group] The Grazulis eliding proposal: how to incorporateinto CIF?

For CIF1 as a semantic feature, I would suggesst the following
simplified version:

1.  A text field starts with <whitespace><eol>; and ends with 
<eol>;<whitespace>, where whitespace may be:
   beginning of document
   end of document
   space (<SP>)
   horizontal tab (<HT>)

2.  If the first characters immediately after the opening
<shiteapce><eol>; are an arbitrary combination of <SP> and/or <HT>
followed by either one or two reverse solidi, with nothing else on the
line after the one or two reverse other than whitespace , a combination
of prefix handlng and line folding will be applied.  If one reverse
is used, then both prefix handling and line folding will be applied.
If two reverse solidi is used, only prefix handling will be applied.

Just as in the past, a parser would be free to ignore this semantic
feature, simply treating the text field as a text field.

  Herbert J. Bernstein, Professor of Computer Science
    Dowling College, Kramer Science Center, KSC 121
         Idle Hour Blvd, Oakdale, NY, 11769


On Tue, 28 Jun 2011, Herbert J. Bernstein wrote:

> Dear Colleagues,
>  I am sorry that my position was misunderstood.  For CIF2, my vote
> is no on this proposal.
>  Regards,
>    Herbert
> =====================================================
> Herbert J. Bernstein, Professor of Computer Science
>   Dowling College, Kramer Science Center, KSC 121
>        Idle Hour Blvd, Oakdale, NY, 11769
>                 +1-631-244-3035
>                 yaya@dowling.edu
> =====================================================
> On Tue, 28 Jun 2011, James Hester wrote:
>> Dear DDLm group,
>> As none of you have raised any substantial objections to the Grazulis
>> eliding proposal, I think we can consider it accepted. The question now
>> arises as to how it will fit into the CIF framework. I see the following
>> possibilities:
>> (1) As a required protocol for all CIF semicolon-delimited text strings
>> (must be recognised by CIF readers)
>> (2) As an available protocol for all CIF semicolon-delimited text strings
>> (may not be recognised by all CIF readers)
>> (3) As a string type defined in DDLm for use in domain dictionary
>> definitions (only needs to be recognised by domain-specific software)
>> Under option (1), the "official" value of a given semicolon-delimited 
>> string
>> would be unambiguously that which results from decoding the protocol. 
>> Under
>> option (2) there would be two "official" values: the undecoded value and 
>> the
>> decoded value, either of which would be acceptable output for a conformant
>> parser; under option (3) the dictionary determines how to process the 
>> string
>> (identically to interpreting e.g. LaTeX strings today). Under option (3)
>> the "official" value from a CIF parser would be the undecoded value, and 
>> the
>> "official" value after application of the dictionary definition would be 
>> the
>> decoded value.
>> My comments:
>> Option (3) has the formal effect of requiring that either the type of 
>> string
>> delimiter is carried forward to the dictionary layer, so that triple-quote
>> delimited strings are not inadvertently "decoded", or else that the 
>> protocol
>> is applied uniformly across all multi-line string constructs for that
>> particular dictionary type.
>> Option (2) insofar as it involves optional behaviour essentially sidelines
>> the proposal, as CIF writers cannot count on it being understood at the
>> reading end and so cannot use it to encode important information
>> Option (1) imposes extra burdens on CIF parser writers, although as Saulius
>> notes it is not particularly difficult to implement.
>> My preference is either (1) or (3), perhaps inclining towards (3) in order
>> to shift complexity to the dictionary level. If the protocol is seen to be
>> generally useful, it would be reasonable to prefer (1).
>> --
>> T +61 (02) 9717 9907
>> F +61 (02) 9717 3145
>> M +61 (04) 0249 4148
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