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Re: Object iterators

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Den söndag 1 september 2019 kl. 02:12:59 UTC+2 skrev Jonas Thörnvall:
> Well they probably have their use, but i've been googling on web midi api for some months looking for howto ***set*** inputs iterator to a single port.
> 
> inputs = mid.inputs.values();
> 
> for (var input = inputs.next();
>      input && !input.done;
>      input = inputs.next()) {
>     // each time there is a midi message call the onMIDIMessage function
>     input.value.onmidimessage = onMIDIMessage;
> }
> 
> I can't find a single example where one set a single input port without looping thru.
> 
> I do not want to read all inputs port using the iterator, i just want to set one input say port 3.
> 
> 
> I would prefered the inputs in an indexed array, because i just do not get howto pick a single port from the input object iterator.

Found this....
========================
For the record, the Iterator API does not allow you to do this. There is no notion of a "current" object. The Iterator.next() method gives you the next object ... and moves on.

(The ListIterator.previous() and ListIterator.next() methods are analogous. Note that in the ListIterator case, method behaviour is documented in terms of a cursor that denotes a position before / between / after elements in the sequence being iterated.)

The solution is to assign the result of calling it.next() to a temporary variable, as described by the accepted answer
========================

So who implemented this as an object iterator, did i????
It is not clear to me what does  
//This is the midi object i guess holding input and output ports
mid = midi;
//Here it becomes unclear to me WTF is going on?????
inputs = mid.inputs.values();
//It seem like we read out inputs values "that apparently is part of the midi //object, it is monkey syntax basicly inputs.values()

But why the fuck they end up in an iterator "inputs?" had it not been more natural to have them end up in an array so you can pick one????

So is it, I that have implemented this as an iterator, or have some deranged little fuck decided that input ports of midi objects are iterators?????

Because that is where my logic breaks down, i guess the inputs are implemented as iterators but why?????

I mean i have no fucking problem to iterate thru an input ports array in a for loop and no problem to set a single one of those to a listener. Using input.

input.value.onmidimessage = onMIDIMessage;

So who the fuck decided that the input ports should be iterators where i can not pick a port because they are not indexed?

If it was me then tell me where the fuck in the code i did it.
Better yet tell how the fuck to get the ports in an array so i can access them one by one two by two or whatever. 

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Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-08-31 17:12 -0700
  Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-08-31 17:17 -0700
    Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-08-31 17:24 -0700
  Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-01 02:53 -0700
    Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-01 02:59 -0700
      Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-01 03:07 -0700
    Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-01 03:20 -0700
      Re: Object iterators John G Harris <niam@jghnorth.org.uk.invalid> - 2019-09-01 11:59 +0100
        Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-01 05:54 -0700
          Re: Object iterators John G Harris <niam@jghnorth.org.uk.invalid> - 2019-09-02 11:08 +0100
        Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-01 12:54 -0700
          Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-02 02:36 -0700
          Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-02 10:16 -0700
            Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-02 10:19 -0700
            Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-02 10:30 -0700
              Re: Object iterators Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-09-03 23:26 -0700
              Re: Object iterators 1975.nenad@googlemail.com - 2020-05-24 04:21 -0700

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