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    <div class="moz-cite-prefix">On 2013-10-02 13:18, Tony Arcieri
      wrote:<br>
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cite="mid:CAHOTMVL2f6Tx8gK_LG7QGL+C7WY9wWG2Svd2g0yk8ALqMr3Lyw@mail.gmail.com"
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          <div class="gmail_quote">LANGSEC calls this: full recognition
            before processing
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            <div><a moz-do-not-send="true"
                href="http://www.cs.dartmouth.edu/%7Esergey/langsec/occupy/"
                target="_blank">http://www.cs.dartmouth.edu/~sergey/langsec/occupy/</a><br>
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    <br>
    I disagree slightly with langsec.<br>
    <br>
    At compile time you want an extremely powerful language for
    describing data, that can describe any possible data structure.<br>
    <br>
    At run time, you want the least possible power, such that your
    recognizer can only recognize the specified and expected data
    structure.<br>
    <br>
    Thus BER and DER are bad for the reasons given by Langsec, indeed
    they illustrate the evils that langsec condemns, but these
    criticisms do not normally apply to PER, since for PER, the
    dangerously great power exists only at compile time, and you would
    have to work pretty hard to retain any substantial part of that
    dangerously great power at run time.<br>
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