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Re: Base-64 proposal
At 08:12 AM 4/16/97 EDT, Ron Rivest wrote:
>* How do you represent a left brace in augmented 8-bit mode?
> The natural answer is as follows:
> A left brace is octal 173 = binary 01111011
> which breaks into hextets as 011110 11xxxx (x = doesn't matter)
> Then 011110 encodes as "e"
> and 11xxxx encodes as "g" (as one possibility)
> Thus, by writing
> {eg}
> in the augmented 8-bit channel, you get a left brace into the output
> ordinary 8-bit channel.
>
> One could introduce other mechanisms for accomplishing this as well, but
> this is sufficient. One natural alternative would be to let "\{" in the
> augmented channel produce "{" in the output, and "\\" in the input
> produce "\" in the output. But this requires two active characters
> left brace and backslash, which seems overkill. I suggest that we
> not introduce redundant mechanisms.
Another option, since "{" isn't part of the 64-character alphabet,
is to accept "{{" or "{{}" as a left brace. May be more trouble than
it's worth, given that "{eg}" works directly, but it doesn't require
magic behaviour for two different characters.
# Thanks; Bill
# Bill Stewart, +1-415-442-2215 stewarts@ix.netcom.com
# You can get PGP outside the US at ftp.ox.ac.uk/pub/crypto/pgp
# (If this is a mailing list, please Cc: me on replies. Thanks.)
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