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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.forth
Subject: Re: Reverse a string (with xchars)
Date: Sun, 21 Feb 2016 12:07:53 -0800
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Chris Curl <ccurl609@gmail.com> writes:
> Since each unicode UTF-16 character is 2 bytes instead of 1, why
> wouldn't something like this work?

UTF-16 is a variable length encoding, like UTF-8.  Remember there are
more than a million Unicode code points.  So you can't always specify
one with 2 bytes.  Plus as Anton says, there is the issue of composing
characters:

  https://en.wikipedia.org/wiki/Unicode_normalization

That means certain characters with diacritics have multiple encodings
some of which use more than one code point, and you have to handle
reversing them.