[SAGA-RG] Python Bindings

[Andre Merzky]

Hi Ole,

On Fri, Dec 14, 2012 at 12:47 AM, Andre Merzky <andre at merzky.net> wrote:
> Hi Ole,
>
> I think this is the last open item I have from your mails:
>
> On Tue, Nov 13, 2012 at 4:25 PM, Ole Weidner <ole.weidner at rutgers.edu> wrote:
>> Hi Andre,
>>
>> the document says:
>>
>> "The constructor has switched the session and name parameters, each method has a tasktype parameter because NSEntry and NSDirectory subclass Async and a number of methods have a _self suffix added to the method name. The reason of the added suffixes is that NSEntry and NSDirectory have a number of identical methods, but with slightly different meaning. Because overloading is not available and intergrating both methods into one method would result in complicated and user unfriendly implementations, the method names were changed."
>>
>> I am not sure if I agree with that statement.
>>
>> I'm not quite sure why instead of having two individual methods, one of which is not even in GFD.90:
>>
>> is_dir_self (self, tasktype=TaskType.NORMAL)
>> is_dir(self, name, tasktype=TaskType.NORMAL)
>>
>> we can't just implemented it as:
>>
>> is_dir (self, path=None,  tasktype=TaskType.NORMAL)
>>
>> path=None would imply '_self'. I think this would be perfectly intuitive and would better 'map' to the unfortunately overloaded methods defined in GFD.90. Also, 'dynamic typing' is of course considered the preferred idiom to emulate method overloading in Python, which shouldn't really surprise you :P
>>
>> Thoughts?
>
> I actually think you are right - but I am not sure we miss something.
> I'll go through those calls again one by one and will check.

Problem is this: at the moment we have:

      entry.copy_self (tgt)
      dir  .copy_self (tgt)
      dir  .copy      (src, tgt)

And you propose I think to replace this with:

      entry.copy      (tgt)
      dir  .copy      (src=None, tgt)

but dir inherits from entry, and you can't overload on different
signatures in python - so that would be invalid.  The alternative
would be to replace with:

      entry.copy      (src=None, tgt)
      dir  .copy      (src=None, tgt)

and to allways throw if a src is specified on an entry (which is not a
dir) -- but that is (a) ugly, and (b) tedious to implement.

Makes sense?  Any better idea?


Thanks, Andre.


>> - Ole
>>
>> On Nov 12, 2012, at 15:51 , Andre Merzky <andre at merzky.net> wrote:
>>
>>> They are awefull all right, but I don't see a better way.  Please have
>>> a look at the the repository -- under pysaga/doc/ you'll see
>>> masterthesis-paul.pdf which motivates that decision quite nicely.  You
>>> probably should go over that doc anyway.
>>>
>>> Best, Andre.
>>>
>>>
>>> On Mon, Nov 12, 2012 at 8:43 PM, Ole Weidner <ole.weidner at rutgers.edu> wrote:
>>>> Hi Andre,
>>>>
>>>> can you please lay out the arguments for the existence of these abominable is_dir_self, is_link_self, etc. constructs? (With some example code, if possible). They look beyond awful and are, btw. a violation of GFD.90 ;-) Let's see if we can come up with something better!
>>>>
>>>> Thanks!
>>>> Ole
>>>>
>>>>
>>>> On Nov 12, 2012, at 14:33 , Andre Merzky <andre at merzky.net> wrote:
>>>>
>>>>> Hi Ole,
>>>>>
>>>>> On Mon, Nov 12, 2012 at 7:40 PM, Ole Weidner <ole.weidner at rutgers.edu> wrote:
>>>>>> Hi Andre, All
>>>>>>
>>>>>> I was just thinking through some practical / convenient improvements for the Python Language bindings. Do you think it would make sense to allow creation of a saga.job.Description from a dictionary, e.g.,
>>>>>>
>>>>>> jd = saga.job.Description({'Executable':'/bin/sleep', 'Arguments':['60']})
>>>>>
>>>>> I should have added that in the bindings - the implementation allows
>>>>> that already.  Thanks!
>>>>>
>>>>>
>>>>>> IMHO this would be a very nice, optional addition. In conjunction with the already existing attributes_as_dict(), the API would become more 'symmetric' and would allow not only serialization but also convenient de-serialization.
>>>>>>
>>>>>> Also, *please* rename attributes_as_dict() to as_dict(). The attribute_ prefix is redundant (Attributes.attributes_as_dict()) and as_dict() is just more commonly used.
>>>>>
>>>>>
>>>>> Makes sense.
>>>>>
>>>>> Best, Andre.
>>>>>
>>>>>
>>>>>> Cheers,
>>>>>> Ole
>>>>>>
>>>>>> On Nov 9, 2012, at 20:32 , Andre Merzky <andre at merzky.net> wrote:
>>>>>>
>>>>>>> Yes, sure!  I am still working on the parameter
>>>>>>> types/names/documentation, and will send it around as soon as that is
>>>>>>> done.
>>>>>>>
>>>>>>> The sources are as always in the redmine git.
>>>>>>>
>>>>>>> Best, Andre.
>>>>>>>
>>>>>>>
>>>>>>> On Fri, Nov 9, 2012 at 8:23 PM, Steve Fisher <dr.s.m.fisher at gmail.com> wrote:
>>>>>>>> Andre,
>>>>>>>> Will you circulate a new PDF when you want us to read it again?
>>>>>>>> Steve
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Nothing is really difficult...
>>>>>>> --
>>>>>>> saga-rg mailing list
>>>>>>> saga-rg at ogf.org
>>>>>>> https://www.ogf.org/mailman/listinfo/saga-rg
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Nothing is really difficult...
>>>>
>>>
>>>
>>>
>>> --
>>> Nothing is really difficult...
>>
>
>
>
> --
> Nothing is really difficult...



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