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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 12:56:06 -0800
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Chris Curl <ccurl609@gmail.com> writes:
> each "char" on the aux stack would have the number of bytes needed,
> followed by the actual bytes. 'A' would be (65 00 02 <-- TOS). a coded
> char would look like this: (30 03 65 00 04) or whatever.

Actually you don't need that overhead.  You can just build up an array
in forward order, but reverse the encoded bytes for each character.  So
if the encoding is (30 03 64 00) then you'd write (00 64 03 30).  After
doing this with all the chars, you'd scan the array backwards, parsing
the encodings from the reversed stream.  In fact you can do this in
place, with no auxiliary storage other than a few bytes to read a single
encoding and reverse it.