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From: Alexander Skobelev <al.skobelev@gmail.com>
Newsgroups: comp.lang.forth
Subject: Re: FORTH LITE TUTORIAL based on MPE VFX
Date: Thu, 26 Jun 2014 11:30:05 +0400
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Ron Aaron <rambamist@gmail.com> writes:

> On 06/26/2014 09:45 AM, Alexander Skobelev wrote:
>
>> I suppose that can be done by using a count of variable size. For
>> example, we can store the length of count in 2 high bits of it:
>> 
>> 00 - count is 1 byte and maximum length is 2^6-1 = 63 
>> 01 - count is 2 bytes and maximum length is 2^6 * 256 + 255 = 16383
> ...
>
> I had considered doing that in Reva, but figured the extra complexity of
> decoding a count byte did not justify the small space savings per
> string.  Instead I went with 'short' and 'long' strings.  My latest
> efforts are all 'long' strings...

Well I'd rather also leave one bit to mark a count to be one byte's
length or in a cell size. In this case I would have 127 bytes or
whatever limited by cell size. And decoding is seems not to be very
complex: you always read the whole cell and (on big-endian architecture)
just shift the count to get one byte value if the flag is not set of
just mask the high byte if it's set . For little endian architecture it
seems better to store the flag in lower bit in the first byte of
counter. Then always rshift the count by 1.