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Re: Playup Event list hangs

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Den torsdag 26 april 2018 kl. 12:23:44 UTC+2 skrev Jonas Thörnvall:
> Den torsdag 26 april 2018 kl. 11:03:28 UTC+2 skrev Evertjan.:
> > =?UTF-8?Q?Jonas_Th=C3=B6rnvall?= <jonas.thornvall@gmail.com> wrote on 26
> > Apr 2018 in comp.lang.javascript: 
> > 
> > > I have a list of timings where each time refer to playup of a midinotes.
> > > See noteOnMessage below.
> > > 
> > > waitEv is a list of "wait times" between events, it is already
> > > precalculated i checked it is correct. I keep waitlists "timings" in
> > > sync with the events by simply step forward y++. 
> > > 
> > > I probably do not understand how the recursive call i tried to implement
> > > work, because it hangs after second event/note is played? 
> > 
> > Methinks you do not understand proper debugging,
> > as viewing the value of y in each recursion would have given it away.
> >  
> > > function doPlayup(y) {
> > >     if (waitEv.length) {
> > >         var waittime = waitEv.shift();
> > >         console.log("Waiting: " + waittime);
> > >         noteOnMessage = [track[tracknr].midiMess[y].data0,
> > >         track[tracknr].midiMess[y].data1,
> > >         track[tracknr].midiMess[y].data2]; output.send(noteOnMessage); 
> > >         document.getElementById("keystream").value=waitEv[y];
> > >         y++; 
> > >         setTimeout(doPlayup, waittime);
> > >     } 
> > >}
> > 
> > Your function is not recursive in the sense of scope,
> > as the setTimeout() does not conduct the nonglobal y value.
> > 
> > perhaps it would 'work' like this:
> > 
> > let y=17;
> > doPlayup();
> > 
> > function doPlayup() {
> > .....
> > };
> > 
> > but then, global variables are prone to misconceptions.
> > 
> > -- 
> > Evertjan.
> > The Netherlands.
> > (Please change the x'es to dots in my emailaddress)
> 
> Thanks for the advice, Evertjan
> 
> I am not used to these types of self referencing functions.
> And i try to figure out howto get ***the last note*** played?
> But it does not behave the way i expect.
> 
>  pyp=-1;
>  doPlayup();
>  noteOnMessage = [track[tracknr].midiMess[pyp].data0,        track[tracknr].midiMess[pyp].data1, track[tracknr].midiMess[pyp].data2]; 
>  output.send(noteOnMessage);
> 
> function doPlayup() {
>     if (waitEv.length) {
>         var waittime = waitEv.shift();
>         console.log("Waiting: " + waittime);
>         if (pyp>-1) 
>         {
>         noteOnMessage = [track[tracknr].midiMess[pyp].data0, track[tracknr].midiMess[pyp].data1, track[tracknr].midiMess[pyp].data2]; 
>         output.send(noteOnMessage); 
>         }
>         pyp++; 
>         setTimeout(doPlayup, waittime); 
>     } 
> }

Well of course i could use the ugly method adding a last note patch message, put a tail on it. Maybe shift just is not a good use in this case? What kind of loop is preferable for this type of problem? 
And i am a bit curious how good programmers use shift in cases like this?

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Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-26 01:47 -0700
  Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-26 01:57 -0700
    Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-26 02:27 -0700
  Re: Playup Event list hangs "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2018-04-26 11:02 +0200
    Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-26 03:23 -0700
      Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-27 07:13 -0700
        Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-27 07:25 -0700
          Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-27 07:30 -0700
            Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-29 12:59 -0700
              Re: Playup Event list hangs "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2018-04-29 22:14 +0200
                Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-29 15:45 -0700
                Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-29 15:47 -0700
                Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-29 16:39 -0700
                Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-29 16:57 -0700
                Re: Playup Event list hangs Jonas Thörnvall <jonas.thornvall@gmail.com> - 2018-04-29 17:06 -0700

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