[Swift-devel] [Bug 291] New: Add a exists() function to test for file existence

[John Dennis]

On Apr 1, 2011, at 12:25 PM, Michael Wilde wrote:

> John, I cc'ed you to confirm that the function is exactly what you  
> were looking for, and that the simple code below matches exactly the  
> requirement thats driving this feature request.
>
> Can you confirm that both of these are true?

Michael,

	So assuming that there is a logical negation operator in Swift the  
function you describe matches my requirements.

Thanks,
John


> We just want to make sure that we understand the need and determine  
> if the proposed exists() function is the best way to address it.  
> From your comment below, I was not quite sure if exists() is exactly  
> the right approach here.
>
> Thanks,
>
> Mike
>
>
> ----- Original Message -----
>> Michael,
>>
>> This type of function would be great to have.
>>
>> John
>> On Apr 1, 2011, at 11:51 AM, Michael Wilde wrote:
>>
>>> Basically as far as I understand: the presence or absence of a
>>> particular data file within the inout dataset is to be used to
>>> determine whether the code to process that dataset subsection gets
>>> invoked or not:
>>>
>>> if (exists("extra.data")) {
>>>    DataFile extraInput<"extra.data">;
>>>    extraResult = analyze(extraInput);
>>> }
>>>
>>> The above is my assumption based on a phone call. We can and should
>>> verify the assumption with a simple example.
>>>
>>> I also thought we can try this today by seeing if extraInput can be
>>> an array, mapped to zero items if nothing to do and 1 item if
>>> something to do. That would at least let us test the use case.
>>>
>>> John, can you verify if the example Swift lines above are what you
>>> are looking for here?
>>>
>>> - Mike
>>>
>>> ----- Original Message -----
>>>> On Fri, 2011-04-01 at 10:51 -0500, Michael Wilde wrote:
>>>>
>>>>> - we should first verify that exists() will solve the NCAR need in
>>>>> a
>>>>> sufficiently clean way
>>>>
>>>> I think this is important. Can we get a description of the problem
>>>> instead of a (otherwise) random proposal for a solution?
>>>
>>> --
>>> Michael Wilde
>>> Computation Institute, University of Chicago
>>> Mathematics and Computer Science Division
>>> Argonne National Laboratory
>>>
>
> -- 
> Michael Wilde
> Computation Institute, University of Chicago
> Mathematics and Computer Science Division
> Argonne National Laboratory
>