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    <div class="moz-cite-prefix">Great, here is the change I'm making to
      address this:</div>
    <blockquote>
      <div class="moz-cite-prefix">Protocol designers:</div>
      <div class="moz-cite-prefix">
        <ul>
          <li>If possible, mandate use of UTF-8 without a BOM; diagnose
            the presence of a BOM in consumed text as an error, and
            produce text without a BOM.</li>
          <li>Otherwise, if possible, mandate use of UTF-8 with or
            without a BOM; accept and discard a BOM in consumed text,
            and produce text without a BOM.</li>
          <li>Otherwise, if possible, use UTF-8 as the default encoding
            with use of other encodings negotiated using information
            other than a BOM; accept and discard a BOM in consumed text,
            and produce text without a BOM.</li>
          <li>Otherwise, require the presence of a BOM to differentiate
            UTF-8 encoded text in both consumed and produced text<b><font
                color="#009900"> unless the absence of a BOM would
                result in the text being interpreted as an ASCII-based
                encoding and the UTF-8 text contains no non-ASCII
                characters (the exception is intended to avoid the
                addition of a BOM to ASCII text thus rendering such text
                as non-ASCII)</font></b>. This approach should be
            reserved for scenarios in which UTF-8 cannot be adopted as a
            default due to backward compatibility concerns.<br>
          </li>
        </ul>
      </div>
    </blockquote>
    <div class="moz-cite-prefix">Tom.<br>
    </div>
    <div class="moz-cite-prefix"><br>
    </div>
    <div class="moz-cite-prefix">On 10/12/20 8:40 AM, Alisdair Meredith
      wrote:<br>
    </div>
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      cite="mid:A708823E-26F0-4C4C-85F7-F24EB32215C4@me.com">
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      That addresses my main concern.  Essentially, best practice (for
      UTF-8) would be no BOM unless the document contains code points
      that require multiple code units to express.
      <div class=""><br class="">
      </div>
      <div class="">AlisdairM<br class="">
        <div><br class="">
          <blockquote type="cite" class="">
            <div class="">On Oct 11, 2020, at 23:22, Tom Honermann <<a
                href="mailto:tom@honermann.net" class=""
                moz-do-not-send="true">tom@honermann.net</a>> wrote:</div>
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              <div class="">
                <div class="moz-cite-prefix">On 10/10/20 7:58 PM,
                  Alisdair Meredith via SG16 wrote:<br class="">
                </div>
                <blockquote type="cite"
                  cite="mid:263C91E2-8EB6-4102-981D-80A1CC44F45D@me.com"
                  class="">
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                  One concern I have, that might lead into rationale for
                  the current discouragement,
                  <div class="">is that I would hate to see a best
                    practice that pushes a BOM into ASCII files.</div>
                  <div class="">One of the nice properties of UTF-8 is
                    that a valid ASCII file (still very common) is</div>
                  <div class="">also a valid UTF-8 file.  Changing best
                    practice would encourage updating those</div>
                  <div class="">files to be no longer ASCII.</div>
                </blockquote>
                <p class="">Thanks, Alisdair.  I think that concern is
                  implicitly addressed by the suggested resolutions, but
                  perhaps that can be made more clear.  One possibility
                  would be to modify the "protocol designer" guidelines
                  to address the case where a protocol's default
                  encoding is ASCII based and to specify that a BOM is
                  only required for UTF-8 text that contains non-ASCII
                  characters.  Would that be helpful?<br class="">
                </p>
                <p class="">Tom.<br class="">
                </p>
                <blockquote type="cite"
                  cite="mid:263C91E2-8EB6-4102-981D-80A1CC44F45D@me.com"
                  class="">
                  <div class=""><br class="">
                  </div>
                  <div class="">AlisdairM<br class="">
                    <div class=""><br class="">
                      <blockquote type="cite" class="">
                        <div class="">On Oct 10, 2020, at 14:54, Tom
                          Honermann via SG16 <<a
                            href="mailto:sg16@lists.isocpp.org" class=""
                            moz-do-not-send="true">sg16@lists.isocpp.org</a>>
                          wrote:</div>
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                            <p class="">Attached is a draft proposal for
                              the Unicode standard that intends to
                              clarify the current recommendation
                              regarding use of a BOM in UTF-8 text. 
                              This is follow up to <a
                                moz-do-not-send="true"
                                href="https://corp.unicode.org/pipermail/unicode/2020-June/008713.html"
                                class="">discussion on the Unicode
                                mailing list</a> back in June.</p>
                            <p class="">Feedback is welcome.  I plan to
                              <a moz-do-not-send="true"
                                href="https://www.unicode.org/pending/docsubmit.html"
                                class="">submit</a> this to the UTC in a
                              week or so pending review feedback.<br
                                class="">
                            </p>
                            <p class="">Tom.<br class="">
                            </p>
                          </div>
                          <span
                            id="cid:958C9297-66AC-4D88-8F0B-577B8BA2589E@nyc.rr.com"
                            class=""><Unicode-BOM-guidance.pdf></span>--
                          <br class="">
                          SG16 mailing list<br class="">
                          <a href="mailto:SG16@lists.isocpp.org"
                            class="" moz-do-not-send="true">SG16@lists.isocpp.org</a><br
                            class="">
                          <a class="moz-txt-link-freetext"
                            href="https://lists.isocpp.org/mailman/listinfo.cgi/sg16"
                            moz-do-not-send="true">https://lists.isocpp.org/mailman/listinfo.cgi/sg16</a><br
                            class="">
                        </div>
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