Re: Language feature selection

From	Don Y <blockedofcourse@foo.invalid>
Newsgroups	comp.arch.embedded
Subject	Re: Language feature selection
Date	2017-03-12 17:00 -0700
Organization	A noiseless patient Spider
Message-ID	<oa4na1$oem$1@dont-email.me> (permalink)
References	(10 earlier) <oa1kes$9lm$1@dont-email.me> <oa3qfe$16oc$1@gioia.aioe.org> <oa4609$qm4$1@dont-email.me> <oa4f2p$r0k$1@dont-email.me> <oa4iaj$6db$1@dont-email.me>

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On 3/12/2017 3:36 PM, Dimiter_Popoff wrote:

> my point is that instead of trying to "port" the old code it is
> much easier to simply emulate the old processor instruction set
> _completely_, like I did with the 6809. People just overlook
> it. And, like I said, the entire thing was 45 kilobytes (and the
> actual processor emulation is a fraction of that) of PPC code....
> Even the 6809 - a fairly complex 8 bit CPU - was quite easy
> to emulate on a Power architecture processor with its huge
> register set, all registers being larger than those to emulate etc.
> And processors of that era tend to be well documented, at least
> those I know (Motorolas) used to be.

But Exorcisers/Exormacs are essentially "desktop" machines -- they
run text processing applications, for the most part.  Even the debuggers
are reasonably "rich" applications -- they've got a healthy budget and
sell price that they could command.

> As long as the original code does not do timing loops
> everything runs just fine. If there are timing loops well,
> they have to be taken care of. Not hard to locate.

The problem comes when the timing is *implicit*.  E.g., you
can't just emulate the functionality of the code being
emulated but, also, must emulate the *timing* of that code.

[If you could do this, then timing loops wouldn't be an issue]

E.g., there were arcade pieces (video/pinball) that would
sit in very tight loops effectively shifting *bits* out
as fast as the processor could manage (because the hardware
was designed by someone ignorant of the *software* issues!).

loop
    sample bit
    if bit HI
       output HI
    else
       output LO
    repeat

Not only do you have to emulate the "time around the loop"
(i.e., each repetition) AND match that of the original
execution time (otherwise, you're altering the frequency
component of the generated "bit stream"), *but*, you also have
to ensure the time between one "output HI" and the next "output HI"
*or* "output LO" remains constant -- otherwise you're introducing
clock jitter.

Then, wrap this in a bigger loop to enumerate all of the bits in
a particular byte:

bigloop:
    fetch byte
    bitcount = 8

loop:
    sample bit
    if bit HI
       output HI
    else
       output LO
    bitcount--
    repeat if not zero

    advance pointer
    bytecount--
    repeat bigloop if not done

And the time from output of the last bit of one byte to
the output of the first bit of the next byte must now satisfy
the same inter-bit time as between any two bits within a
single byte.

[If using this to generate audio, clock jitter can beat
through the signal annoyingly]

If you look through some of my old (ancient) code, you'll
often see numbers in parens adjacent to each instruction
(ASM) indicating the number of clock cycles.  This code stanza
will be bracketed with comments like:
     // set output to desired state
     ...
     //      (5)
     //      (10/12)
     //      (4)
     ...
     // at least (19) clock cycles have elapsed -- sufficient
     // delay for Fosc <= 12.3MHz
I.e., instead of spinning in a loop, I was "doing work" that needed
to be done and using the side effect (elapsed time) of that work
to provide my delay.

If you just look at the object/ROM image, you'd not know that this
was happening for a deliberate reason.

For really short delays, there isn't often a practical alternative.
OTOH, old processors had far more predictable "best case" timings
(if they happened to "run long", no problem -- you're looking for
AT LEAST some minimum delay)

> Then emulating on a much faster CPU makes life easier;
> you can just include some virtual machinery in the emulation,
> e.g. trap read/writes to old peripheral addresses and handle
> them on the new CPU using its peripherals - and its power
> (I did not do that IIRC, I just modified a little the ROM
> entry points - did have the sources as I had written it - so
> that say for disk accesses via the old floppy disk controller
> the thing traps and uses a memory image for a floppy disk
> (the largest one was 512 kilobytes....).
>
> A 400 MHz Power core (603e derivative) runs about 50 times
> faster than two 2 MHz 6809 CPU-s could run in parallel,
> without the emulation being particularly tricky or pushed,
> just the old processor took a lot of cycles to do things.
> They all did.
>
> Mind you, I have done the "porting" as well - when performance
> mattered. This is how I started vpa - it assembled CPU32 sources
> into PPC object code. The effort did not take me a few weeks
> as it did with the 6809 emulation, it took me about _a year_,
> the vpa sources are 880 kilobytes - I have been progressing at
> half my average programming rate which is about 150k/month...
> Much much harder than the emulation (well, this was the tool
> creation of course, not really comparable the two things).

Thread

Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-05 16:03 -0700
  Re: Language feature selection Wouter van Ooijen <wouter@voti.nl> - 2017-03-06 08:04 +0100
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-07 10:31 -0700
      Re: Language feature selection Wouter van Ooijen <wouter@voti.nl> - 2017-03-07 23:29 +0100
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-08 02:49 -0700
          Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-08 13:18 +0100
            Re: Language feature selection Wouter van Ooijen <wouter@voti.nl> - 2017-03-08 16:58 +0100
            Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-08 10:35 -0700
              Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-08 22:07 +0100
  Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-06 08:40 +0100
    Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-06 10:31 +0100
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-06 08:47 -0700
      Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-06 21:33 +0100
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-06 13:44 -0700
          Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-07 12:24 +0100
            Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-07 09:34 -0700
              Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-08 10:14 +0100
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-08 10:37 -0700
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-08 22:09 +0100
    Re: Language feature selection Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2017-03-06 22:50 +0200
      Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-07 12:31 +0100
    Re: Language feature selection rickman <gnuarm@gmail.com> - 2017-03-07 14:45 -0500
  Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-06 08:39 +0000
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-06 08:39 -0700
      Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-06 17:27 +0000
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-06 13:30 -0700
  Re: Language feature selection Dimiter_Popoff <dp@tgi-sci.com> - 2017-03-06 11:11 +0200
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-06 13:38 -0700
      Re: Language feature selection Dimiter_Popoff <dp@tgi-sci.com> - 2017-03-07 12:18 +0200
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-07 10:28 -0700
  Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-06 13:33 -0500
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-06 13:36 -0700
      Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-06 22:15 -0500
        Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-06 22:22 -0500
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-07 00:27 -0700
          Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-08 12:20 -0500
            Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-08 11:23 -0700
              Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-10 13:43 -0500
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 16:49 -0700
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-11 04:17 -0500
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-11 12:33 -0700
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-12 18:08 -0400
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-12 17:25 -0700
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-15 21:05 -0400
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-16 17:23 -0700
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-17 23:59 -0400
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-17 23:25 -0700
                Re: Language feature selection Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2017-03-18 12:05 +0200
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-18 04:04 -0700
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-18 04:39 -0700
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-18 03:55 -0700
                Re: Language feature selection upsidedown@downunder.com - 2017-03-18 16:00 +0200
                Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-11 16:35 -0600
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-11 15:39 -0700
  Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-06 18:59 +0000
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-06 12:36 -0700
  Re: Language feature selection Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2017-03-07 19:02 +0000
    Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-07 19:18 +0000
      Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-07 19:19 +0000
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-07 12:38 -0700
  Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-07 22:10 -0600
    Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-07 20:35 -0800
      Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-08 20:43 -0600
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-07 23:48 -0700
      Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-08 20:48 -0600
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-08 21:15 -0700
        Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-09 01:33 -0800
        Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-09 14:47 +0000
          Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-09 16:40 +0100
            Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-09 16:15 +0000
              Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-09 22:04 +0100
                Re: Language feature selection John Devereux <john@devereux.me.uk> - 2017-03-10 07:46 +0000
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-10 13:21 +0100
              Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-09 17:57 -0600
                Re: Language feature selection Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2017-03-10 11:16 +0200
        Re: Language feature selection Jacob Sparre Andersen <jacob@jacob-sparre.dk> - 2017-03-10 20:39 +0100
          Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-10 13:32 -0800
            Re: Language feature selection Niklas Holsti <niklas.holsti@tidorum.invalid> - 2017-03-11 14:58 +0200
              Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-13 13:02 +0100
    Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-08 10:46 +0100
      Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-08 20:33 -0600
        Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-09 11:08 +0100
          Re: Language feature selection Britt <britt.snodgrass@gmail.com> - 2017-03-09 07:04 -0800
            Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-09 16:36 +0100
              Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-09 16:11 +0000
              Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-09 12:06 -0600
              Re: Language feature selection Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2017-03-09 19:26 +0100
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-09 22:08 +0100
            Re: Language feature selection Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2017-03-09 19:04 +0000
              Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-09 15:34 -0700
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-09 15:40 -0700
                Re: Language feature selection Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> - 2017-03-10 14:19 +0000
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 11:10 -0700
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 11:49 -0700
        Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-09 18:00 -0600
    Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-09 17:54 -0600
      Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-09 18:54 -0600
        Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-10 04:07 +0000
          Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-10 08:07 -0600
        Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-10 13:59 +0100
      Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-10 08:17 +0000
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 11:24 -0700
          Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-10 19:09 +0000
            Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 12:33 -0700
              Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-10 23:25 +0000
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-10 20:22 -0500
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 01:32 +0000
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-10 18:16 -0800
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 09:59 +0000
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-11 02:23 -0800
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 11:13 +0000
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-11 14:28 -0500
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-11 17:20 -0500
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-12 16:26 -0400
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-12 21:46 +0100
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-12 23:15 +0000
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-13 14:14 -0400
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-13 18:48 +0000
                Re: Language feature selection "Brian G. Lucas" <bagel99@gmail.com> - 2017-03-13 15:17 -0500
                Re: Language feature selection Niklas Holsti <niklas.holsti@tidorum.invalid> - 2017-03-13 23:17 +0200
                Re: Language feature selection "Brian G. Lucas" <bagel99@gmail.com> - 2017-03-13 17:27 -0500
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-13 17:10 -0700
                Re: Language feature selection Niklas Holsti <niklas.holsti@tidorum.invalid> - 2017-03-14 10:11 +0200
                Re: Language feature selection "Brian G. Lucas" <bagel99@gmail.com> - 2017-03-14 12:23 -0500
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-14 13:27 +0100
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-14 13:30 -0400
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-14 22:03 +0100
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-14 17:24 -0400
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-11 07:19 -0600
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 19:43 +0000
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-12 09:28 -0600
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-12 15:15 -0400
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-12 19:38 +0000
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-10 18:08 -0800
                Re: Language feature selection George Neuner <gneuner2@comcast.net> - 2017-03-11 04:22 -0500
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 10:02 +0000
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-11 02:22 -0800
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 11:07 +0000
          Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-10 14:30 -0600
            Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-10 13:37 -0800
              Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-10 16:30 -0600
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-10 18:14 -0800
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-11 07:46 -0600
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-11 12:53 -0700
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-12 09:45 -0600
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-12 11:56 -0700
                Re: Language feature selection Dimiter_Popoff <dp@tgi-sci.com> - 2017-03-12 21:05 +0200
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-12 14:40 -0700
                Re: Language feature selection Dimiter_Popoff <dp@tgi-sci.com> - 2017-03-13 00:36 +0200
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-12 17:00 -0700
                Re: Language feature selection Robert Wessel <robertwessel2@yahoo.com> - 2017-03-13 16:50 -0500
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-13 17:08 -0700
                Re: Language feature selection Robert Wessel <robertwessel2@yahoo.com> - 2017-03-13 20:51 -0500
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-13 20:31 -0700
                Re: Language feature selection Robert Wessel <robertwessel2@yahoo.com> - 2017-03-14 21:45 -0500
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-14 21:16 -0700
                Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-11 16:40 -0600
            Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 15:10 -0700
              Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-10 16:42 -0600
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 17:02 -0700
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 00:46 +0000
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-11 13:05 -0700
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 21:58 +0000
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-11 15:19 -0700
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-11 23:27 +0000
                Re: Language feature selection Walter Banks <walter@bytecraft.com> - 2017-03-10 20:14 -0600
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-11 12:16 -0700
        Re: Language feature selection Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2017-03-10 20:40 +0100
          Re: Language feature selection Wouter van Ooijen <wouter@voti.nl> - 2017-03-10 22:28 +0100
  Re: Language feature selection Jacob Sparre Andersen <jacob@jacob-sparre.dk> - 2017-03-10 20:03 +0100
    Re: Language feature selection Grant Edwards <invalid@invalid.invalid> - 2017-03-10 19:48 +0000
      Re: Language feature selection Jacob Sparre Andersen <jacob@jacob-sparre.dk> - 2017-03-13 21:25 +0100
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-10 13:03 -0700
      Re: Language feature selection Jacob Sparre Andersen <jacob@jacob-sparre.dk> - 2017-03-13 21:40 +0100
        Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-13 14:35 -0700
          Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-14 01:06 +0000
            Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-13 19:23 -0700
              Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-14 08:48 +0000
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-14 02:14 -0700
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-14 09:33 +0000
                Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-14 09:21 -0700
                Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-17 06:01 -0500
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-17 11:39 +0000
                Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-17 07:16 -0500
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-17 13:49 +0000
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-17 11:03 -0700
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-17 19:21 +0100
                Re: Language feature selection Paul Rubin <no.email@nospam.invalid> - 2017-03-17 11:34 -0700
                Re: Language feature selection David Brown <david.brown@hesbynett.no> - 2017-03-17 20:26 +0100
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-17 20:07 +0000
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-17 20:29 +0000
                Re: Language feature selection Les Cargill <lcargill99@comcast.com> - 2017-03-17 19:19 -0500
                Re: Language feature selection Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-18 08:18 +0000
            Re: Language feature selection Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2017-03-14 21:20 +0100
  Re: Language feature selection jim.brakefield@ieee.org - 2017-03-10 18:46 -0800
    Re: Language feature selection Niklas Holsti <niklas.holsti@tidorum.invalid> - 2017-03-11 15:41 +0200
      Re: Language feature selection jim.brakefield@ieee.org - 2017-03-11 14:20 -0800
        Re: Language feature selection upsidedown@downunder.com - 2017-03-12 00:54 +0200
          Re: Language feature selection jim.brakefield@ieee.org - 2017-03-12 18:08 -0700
            Re: Language feature selection upsidedown@downunder.com - 2017-03-13 23:36 +0200
          Re: Language feature selection Robert Wessel <robertwessel2@yahoo.com> - 2017-03-13 17:03 -0500
    Re: Language feature selection Don Y <blockedofcourse@foo.invalid> - 2017-03-11 14:21 -0700

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