[Gambas-user] My confusion Re: New Syntax, SUPER && !comprehension(mine) Re.: SUPER example at gambasdoc

Fabien Bodard gambas.fr at ...626...
Mon May 12 23:27:50 CEST 2014 

Le 12 mai 2014 23:19, "Stephen" <sbungay at ...3301...> a écrit :
>
> Well, now I am aware of the inconsistency so when I see it I'll know
> what is being done and double check the datatype to see what is being
> manipulated. I still think it is bad form; but that's just me.

You will see that is a terrific and efficient form ... In the future

> On 05/12/2014 01:18 PM, Fabien Bodard wrote:
> > yes and that's why you need to use good naming for your variables !!
> >
> >
> > Dim cX as New Collection
> >
> > Dim aX as New Integer[]
> >
> >
> > You now all classes can use that syntax too :
> >
> > MyClass[0]=toto
> >
> > If the special procedure _put(index as integer) is declared. The []
> > are not specific to the arrays or collections.
> >
> >
> >
> >
> >
> > 2014-05-12 18:31 GMT+02:00 Stephen<sbungay at ...3301...>:
> >>    Hi Fabien!
> >>
> >>
> >>> Le 12 mai 2014 12:12, "Stephen"<sbungay at ...3301...>   a écrit :
> >>>> Hi Tobias, thanks for the reply, things got busy and I'm just getting
> >>>> back to the keyboard.
> >>>>
> >>>> It was how things were being done in the (broken) GAMBASDOC example
> >>>> confused me.
> >>>> In one area the programmer is using the Add method of a string object
> >>>> array, but this line
> >>>>
> >>>> $cPos[Key] = $aKey.Count
> >>>>
> >>>> caused me to pause.
> >>>>
> >>>> My thought at the time of reading it went something like this:
> >>>>
> >>>> "What being done here? There's been no use of the Add method! How can
> >>>> you reference
> >>>> something that doesn't yet exist and why is no error being thrown for
> >>>> doing so"?
> >>> A collection automatically add an non existant entry ... Or just
assign the
> >>> new value... If the value is null then the entry is deleted.
> >>>
> >> Yes, it is a convenient way of adding, editing, or deleting items from
a
> >> collection,
> >> but I personally will never use it. Why? Because IMHO it introduces
> >> inconsistencies in the language. The short form of adding, updating, or
> >> deleting items to/from a collection exactly mimics the syntax of
assigning
> >> a value to an array element, but they can not actually be used the
same way;
> >>
> >> ' This throws an error
> >> DIM X AS NEW Integer[]
> >> X[0] = 1
> >>
> >>
> >> ' This doesn't
> >> DIM X AS NEW Collection
> >> X[0] = 1
> >>
> >> Even GambasDoc lead me astray as it says a collection is a "class" that
> >> "acts like a read
> >> <http://gambasdoc.org/help/comp/gb/collection/_get?view>  / write
> >> <http://gambasdoc.org/help/comp/gb/collection/_put?view>  array.", but
it
> >> doesn't does it? The second example above doesn't work with an array
> >> unless the element has been Added
> >> first, which IMHO is as it should be.
> >>
> >>>> Now I think that the Add method of the collection is being implicitly
> >>>> called using older
> >>>> non OOP array assignment syntax.
> >>>>
> >>>> IMHO enforcing the explicit use of the object's Add method
> >>>>
> >>>> $cPos.Add($aKey.Count, Key)
> >>>>
> >>>> might take more keystrokes, but it definitely better communicates
what
> >>>> is being manipulated (an object vs an array) and what is being done
> >>>> (Adding).
> >>>>
> >>>>
> >>>> On 05/08/2014 09:28 AM, Tobias Boege wrote:
> >>>>> On Thu, 08 May 2014, Stephen wrote:
> >>>>>>       Looking at the thread "New syntax for using variables
arguments in
> >>> a
> >>>>>> function call" I realized that I needed to really brush up on my
> >>>>>> somewhat marginal understanding of the evolving (a good thing)
GAMBAS
> >>>>>> and OOP. Not fully understanding "SUPER" (I've never used it but
can
> >>> see
> >>>>>> a use for it) I trotted off to Google and the GAMBAS documentation,
> >>>>>> where much reading was done, and (as usual) more questions raised.
> >>>>> If you write a class and inherit from another class, you can
override
> >>>>> methods and properties in your inheriting class. However, sometimes
the
> >>>>> inherited class does a pretty good job already and you don't want to
> >>>>> reinvent the wheel for doing something. That's when Super comes into
> >>> play
> >>>>> because Super knows where the method and property implementations
of the
> >>>>> inherited class (the super class) are. So you can still call
methods of
> >>>>> the super class in your subclass that you have actually just
overridden.
> >>>>>
> >>>>> In the example below, you want to skim data in ListBox' Add()
method but
> >>>>> you don't want to implement the actual addition of a new element so
you
> >>>>> resort to the original ListBox' Add() implementation - which is
> >>> available
> >>>>> as Super.Add() and knows how to do the thing.
> >>>>>
> >>>>>>       Studying the "SUPER" example at
> >>> http://gambasdoc.org/hemp/lang/super,
> >>>>>> I wondered at the purpose of a collection that seems not to be
used but
> >>>>>> once and some syntax in it's use in the example, which didn't make
any
> >>>>>> sense to my old brain. Below is a snippet from the example (where
$cPos
> >>>>>> is a collection, $aKey an Array of String Objects (I think) and
Key a
> >>>>>> string object;
> >>>>>>
> >>>>>> $cPos.Clear
> >>>>>> $cPos[Key] = $aKey.Count
> >>>>>> $aKey.Add(Key)
> >>>>>>
> >>>>>>       OK, the first line clears the collection, got it, and the
last line
> >>>>>> adds the contents of "String" to $aKey, got that.... but what does
the
> >>>>>> second line do? It looks like it is adding the count of elements in
> >>>>>> $aKey to the collection $cPos... but in OOP I would use a method
call
> >>>>>> i.e. $cPos.Add(Key,Key). Oh, and in trying to implement the example
> >>>>>> GAMBAS (3.5.3) complained that "ListBox.Add is incorrectly
overridden".
> >>>>>>
> >>>>> $cPos[Key] = $aKey.Count followed by $aKey.Add(Key) will store the
> >>> *index*
> >>>>> of Key in the $aKey array in the $cPos collection, indexed by the
> >>> *value* of
> >>>>> the key. (Think about it.)
> >>>>>
> >>>>> That means if the user gives you a Key, you can look up the index of
> >>> that
> >>>>> key in the $aKey array using $cPos[Key], i.e. the statement
> >>>>>
> >>>>>      $aKey[$cPos[Key]]
> >>>>>
> >>>>> will always return Key (or raise an error, but see below for that).
This
> >>>>> also explains why the Collection is named $cPos.
> >>>>>
> >>>>> Not sure what that implies or what we can do with it and how
> >>> $cPos.Clear()
> >>>>> fits into the picture because it already deletes that additional
> >>> information
> >>>>> we collected...
> >>>>>
> >>>>> Either I don't get it or the example is just broken (I'd prefer the
> >>> second
> >>>>> option, of course :-)).
> >>>>>
> >>>>> Regards,
> >>>>> Tobi
> >>>>>
> >>>> --
> >>>> Kindest Regards
> >>>> Stephen A. Bungay, Prop.
> >>>> Smarts On Site
> >>>>
> >>>>
> >>>>
> >>>
------------------------------------------------------------------------------
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> >>>> _______________________________________________
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> >>>> Gambas-user at lists.sourceforge.net
> >>>> https://lists.sourceforge.net/lists/listinfo/gambas-user
> >>>
------------------------------------------------------------------------------
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> >>> Instantly run your Selenium tests across 300+ browser/OS combos.
> >>> Get unparalleled scalability from the best Selenium testing platform
available
> >>> Simple to use. Nothing to install. Get started now for free."
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> >>> _______________________________________________
> >>> Gambas-user mailing list
> >>> Gambas-user at lists.sourceforge.net
> >>> https://lists.sourceforge.net/lists/listinfo/gambas-user
> >>
> >> --
> >> Kindest Regards
> >> Stephen A. Bungay, Prop.
> >> Smarts On Site
> >>
> >>
------------------------------------------------------------------------------
> >> "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE
> >> Instantly run your Selenium tests across 300+ browser/OS combos.
> >> Get unparalleled scalability from the best Selenium testing platform
available
> >> Simple to use. Nothing to install. Get started now for free."
> >> http://p.sf.net/sfu/SauceLabs
> >> _______________________________________________
> >> Gambas-user mailing list
> >> Gambas-user at lists.sourceforge.net
> >> https://lists.sourceforge.net/lists/listinfo/gambas-user
> >
> >
>
>
> --
> Kindest Regards
> Stephen A. Bungay, Prop.
> Smarts On Site
>
>
>
------------------------------------------------------------------------------
> "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE
> Instantly run your Selenium tests across 300+ browser/OS combos.
> Get unparalleled scalability from the best Selenium testing platform
available
> Simple to use. Nothing to install. Get started now for free."
> http://p.sf.net/sfu/SauceLabs
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