Thank you! I like this solution. You're right, core modules can often get you most of the way to where you want to go.

That said, it needed some modification to work with the larger battery of tests I have locally. The first thing I noticed is that Encode doesn't always produce a four digit hex entity. I took care of that by allowing the regular expression to match two or four characters. Then came the string that encoded as "Mar&#ed;a; F", so I made the "characters" match only hex digits.

Now the replacement looks like this: 

$s =~ s/&#x([a-f0-9]{2})?([a-f0-9]{2});/'\\u' . ($1||'00') . $2/ieg;

[download]

That still doesn't take care of the problem that ikegami raises. I figure I can preprocess with s/&/&x/g and then back with s/&x/&/g when it's done (or something), but then we're back up to five full scans over the input string. It might still be faster, but I haven't tested that yet.

Thanks again.

In reply to Re^2: Faster utf8 escaping. by kyle
in thread Faster utf8 escaping. by kyle

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.