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Re: DDL Version 2.0.16

John Westbrook (jwest@wormhole.rutgers.edu)
Thu, 22 Jun 1995 11:34:09 -0400 

On Jun 20, 10:20am, Peter Keller wrote:

>
> Dear all,
>
> Unfortunately, constructions such as:
>
>
> save_DATA_BLOCK
>
>     _category.description
> ;
>      Attributes defining the characteristics of a data block.
> ;
>     _category.id                         data_block
>
>
> mean that the DDL is no longer STAR conformant (!) - recall that in the
> STAR specification (Hall and Spadaccini, J. Chem. Inf. Comput. Sci. vol
> 34, p505-508, 1994) we have the definition:
>
>    <data_heading>    ::=  data_<non_blank_char>+

However the definition of <data> is the following:

<data>  ::= <data_name> <data_value> | <data_loop>

I interpret this to mean that an instance of data must include both a
data name and either a data value or data loop.  The definition
for data values do not include the possibility for another instance
of a data header.  I had also interpreted that in section 10a of
J. Chem. Inf. Comput. Sci. 34, p508 Privileged Constructs, that
the restriction in the use of data_, loop_, global_, etc.
applied to the specification of data items (ie. the data name not the
data value).

At any rate, thanks for pointing out this problem.  I am putting a
version of the dictionary on the server that has quoting that you
indicate will allow the DDL to survive the STARbase test.

Regards...

John


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*  John Westbrook                       Ph:  (908) 445-5156                *
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