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Re: [ddlm-group] Space as a list item separator>

I thought you had your vote and had decided not to support commas in
lists, but if it is still being discussed ...

Actually, while I agree that it is probably an error to have ,, for ,.,
it is likely to be a recoverable error, so I have included the option
of such recovery in CIFtbx4 and will be adding it in CBFlib, but in
both cases as conditional on whether commas are allowed.

   -- 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
                  [email protected]
=====================================================

On Thu, 3 Dec 2009, Nick Spadaccini wrote:

> If commas are to be separators in lists or tables then yes they must appear
> within delimited strings only, and are restricted from the character set for
> non-delimited strings -  I didn't include commas in last email on
> non-delimited restrictions.
>
> Depending on the votes we may not need to consider commas as special.
>
> As for adjacent commas there seems to be a view that one should "create
> data" in these situations. Both . and ? have very specific and different
> meanings (though there are erroneously used interchangeably) but above all
> they are user specified values. That is the user is telling you that the
> value is either ? or . Adjacent commas is a error, and in my opinion one
> from which you cannot recover. To infer from [1,2,,3] that the value is ? or
> . is no different to inferring 0, -99 or "blah". Even if it were inferred to
> be ?, what does that mean to a list that is bound to be operationally within
> some dREL code. What does the evaluator do with ? ?
>
> Nick
>
> On 3/12/09 3:00 AM, "Joe Krahn" <[email protected]> wrote:
>
>> I assume that quoting rules are the same: any string containing
>> delimiter characters must be quoted. Normally, that is just whit space,
>> but includes comma in the list context.
>>
>> Also, are adjacent commas invalid, or valid as the undefined ".", or as
>> the unknown "?"?
>>
>> Joe
>>
>> Nick Spadaccini wrote:
>>> Since this issue is not yet fully closed, for clarification as delimiters of
>>> tokens within a compound data type, comma and space are not exactly
>>> equivalent. The delimiters (that are equivalent) are
>>>
>>>  [:space:]+  # --- for white space delimited
>>>
>>>  [:space:]* , [:space:]*  # --- for comma delimited
>>>
>>> [:space:] matches a single whitespace character, * is the Kleene Star
>>> meaning zero (0) or more instances of a matche and + is the Kleene Plus
>>> meaning one (1) or more instances of the match.
>>>
>>> With that qualification, I agree with Herb's assessment.
>>>
>>> On 1/12/09 8:35 PM, "Herbert J. Bernstein" <[email protected]>
>>> wrote:
>>>
>>>> If both comma and space are permitted then I would treat
>>>>
>>>> [1, 2, 3  4 ]   or  [1,2,3 4]
>>>>
>>>> as equivalent and equivalent to
>>>>
>>>> [1 2 3 4] and [1 , 2 , 3 , 4] and [ 1 2 3 4 ]
>>>>
>>>> At least that is the way I have coded CIFtbx and CBFlib.
>>>> =====================================================
>>>>   Herbert J. Bernstein, Professor of Computer Science
>>>>     Dowling College, Kramer Science Center, KSC 121
>>>>          Idle Hour Blvd, Oakdale, NY, 11769
>>>>
>>>>                   +1-631-244-3035
>>>>                   [email protected]
>>>> =====================================================
>>>>
>>>> On Tue, 1 Dec 2009, John Westbrook wrote:
>>>>
>>>>> Could I ask for a clarification of the interpretation of a mixed case
>>>>> such as:
>>>>>
>>>>> [1, 2, 3  4 ]   or  [1,2,3 4]
>>>>>
>>>>> If quote and space are permitted are the above going to satisfy the
>>>>> syntax requiremens?
>>>>>
>>>>> John
>>>>>
>>>>>
>>>>> Herbert J. Bernstein wrote:
>>>>>> First amending the arguments
>>>>>>
>>>>>> To summarise the arguments:
>>>>>>
>>>>>> 1. In favour of both space and comma
>>>>>>    - comma is used in some other non-CIF contexts as a list delimiter
>>>>>>    - comma allows a large subset of lists and arrays to be carried
>>>>>> opaquely in CIF 1 and CIF 1.1 documents.
>>>>>>
>>>>>> 2. Against comma:
>>>>>>    - A single type of separator makes the grammar simpler
>>>>>>    - Space is used everywhere else in CIF as a separator (consistency)
>>>>>>    - Comma can then be used in non-delimited strings
>>>>>>
>>>>>> Then
>>>>>>
>>>>>> I vote for comma and space -- 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
>>>>>>                  [email protected]
>>>>>> =====================================================
>>>>>>
>>>>>> On Tue, 1 Dec 2009, James Hester wrote:
>>>>>>
>>>>>>> Dear CIF2 people: the time has come to vote on the list item separator
>>>>>>> issue.  Firstly: as far as I know, nobody is against space as a
>>>>>>> separator,
>>>>>>> so spaces will be possible list item separators.  Some may be against
>>>>>>> commas, so this vote is on whether or not to allow commas.
>>>>>>>
>>>>>>> To summarise the arguments:
>>>>>>>
>>>>>>> 1. In favour of both space and comma
>>>>>>>    - comma is used in some other non-CIF contexts as a list delimiter
>>>>>>>
>>>>>>> 2. Against comma:
>>>>>>>    - A single type of separator makes the grammar simpler
>>>>>>>    - Space is used everywhere else in CIF as a separator (consistency)
>>>>>>>    - Comma can then be used in non-delimited strings
>>>>>>>
>>>>>>> Space only: Nick, James (Nick is here)
>>>>>>> Comma and Space: ?
>>>>>>>
>>>>>>> On Tue, Dec 1, 2009 at 5:30 PM, James Hester <[email protected]>
>>>>>>> wrote:
>>>>>>>       More specifically, CIF1.1 excludes square brackets as the first
>>>>>>>       character in a non-delimited string.
>>>>>>>
>>>>>>>
>>>>>>> On Tue, Dec 1, 2009 at 9:33 AM, James Hester <[email protected]>
>>>>>>> wrote:
>>>>>>>       Dear Herbert: as CIF 1.1 doesn't define lists, I'm not
>>>>>>>       sure why you suggest that the example below is a valid
>>>>>>>       tag.
>>>>>>>
>>>>>>>       On Tue, Dec 1, 2009 at 12:36 AM, Herbert J. Bernstein
>>>>>>>       <[email protected]> wrote:
>>>>>>>             Sorry something got lost in the prior message.
>>>>>>>              It should have
>>>>>>>             read:
>>>>>>>
>>>>>>>                   Dear Colleagues,
>>>>>>>
>>>>>>>                    Back to the question of commas.
>>>>>>>                    If you accept the desirability of
>>>>>>>                   having a CIF 1.5, commas in lists
>>>>>>>                   become very useful.  Someone with
>>>>>>>                   a CIF 1.1 editor will be able to
>>>>>>>                   prepare a CIF 1.5 file for many
>>>>>>>                   useful cases by doing all lists
>>>>>>>                   with commas and no embedded blanks
>>>>>>>                   as long as they can make their
>>>>>>>                   lists fit on single lines.  In CIF
>>>>>>>                   1.1
>>>>>>>
>>>>>>>                   [[1,2,3],[4,5,6],[7,8,9]]
>>>>>>>
>>>>>>>                   is a valid value for a tag, but
>>>>>>>
>>>>>>>                   [[1 2 3] [4 5 6] [7 8 9]]
>>>>>>>
>>>>>>> is not.
>>>>>>>
>>>>>>>
>>>>>>> No, neither example is a valid CIF 1.1 tag.  CIF 1.1 explicitly
>>>>>>> excludes brackets as the first character of a non-delimited
>>>>>>> string.
>>>>>>>
>>>>>>>
>>>>>>>             Having the option of commas in lists
>>>>>>>             will help to smooth the
>>>>>>>             transition for at least some people.
>>>>>>>
>>>>>>>
>>>>>>>
>
> cheers
>
> Nick
>
> --------------------------------
> Associate Professor N. Spadaccini, PhD
> School of Computer Science & Software Engineering
>
> The University of Western Australia    t: +61 (0)8 6488 3452
> 35 Stirling Highway                    f: +61 (0)8 6488 1089
> CRAWLEY, Perth,  WA  6009 AUSTRALIA   w3: www.csse.uwa.edu.au/~nick
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>
> e: [email protected]
>
>
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