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Re: DDL Version 2.0.16

Peter Keller (bsspak@bath.ac.uk)
Tue, 20 Jun 1995 11:19:23 +0100 (BST) 

On Fri, 9 Jun 1995, John Westbrook wrote:

> 
> Greetings...
> 
> I have placed version 2.0.16 of the DDL on our server.  This version reflects
> a few minor structural changes and my attempt to implement suggestions
> that I have received over the past few months.  Thank you to all have
> contributed comments.

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>+

My own CIF-restricted STAR grammar produces a syntax error at this point, 
and the Star_Base program coredumps (under IRIX 5.2), as it also 
interprets "data_block" as a data heading:

(d)   DATA_NAME
(d)   _category.id
(d)   DATA_HEADING
(d)                            data_block
(e)   Segmentation fault (core dumped)

Data items such as data_block or data_block_group should be quoted, just 
as data items which begin with an underscore are. Here is the diff output 
to correct this:

271c271
<     _category.id                         data_block
---
>     _category.id                        'data_block'
290,291c290,291
<          '_data_block.id'                     data_block          implicit
<          '_data_block_methods.data_block_id'  data_block_methods  implicit
---
>          '_data_block.id'                    'data_block'         implicit
>          '_data_block_methods.data_block_id' 'data_block_methods' implicit
313c313
<     _item.category_id                    data_block
---
>     _item.category_id                   'data_block'
328c328
<     _category.id                         data_block_methods
---
>     _category.id                        'data_block_methods'
1753c1753
<          '_data_block_methods.method_id'     data_block_methods     yes
---
>          '_data_block_methods.method_id'    'data_block_methods'    yes


Regards,
Peter.

========================================================================
Peter Keller.            \ 
Dept. of Biology and      \ "Not even the greatest nonsense is beyond
    Biochemistry,          \  the reach of human invention."
University of Bath,         \ 
Bath, BA2 7AY, UK.           \          --- Ryszard Kapuscinski
------------------------------\-----------------------------------------
Tel. (+44/0)1225 826826 x 4302 | Email: P.A.Keller@bath.ac.uk (Internet)
Fax. (+44/0)1225 826449        |   P.A.Keller%bath.ac.uk@UKACRL (BITNET)
========================================================================