[plt-scheme] 299.404

From: Eli Barzilay (eli at barzilay.org)
Date: Thu Oct 13 23:35:57 EDT 2005

On Oct 13, Felix Klock's PLT scheme proxy wrote:
> The statement you make up above is pretty subjective.  The binary
> format was pretty unreadable, but I managed to hack up some sed
> scripts (well, really just some emacs regexp's) that would help me
> recover student data when they couldn't load a file into DrScheme.
> The point is, a lot of the text was there, it was just intermixed
> with a lot of control characters that, while annoying, could be
> filtered out a lot of the time.
> Is the same true here?


> That is, if something does go wrong, does a developer with a good
> handle on his emacs-fu have a chance of making sense out of the
> corrupted file?  Can someone with a build of 299.404 confirm or deny
> this?

If you've done some recovery work with Emacs, then you've probably
noticed a lot of "^@"s, which indicates small numbers, which specify
block lengths.  The new format has these numbers explicitly now (in
ascii), mixed with the content as byte strings or lists of byte
strings when the contents is too long.

It's probably going to be a little harder to hack regexps for the new
format, but it would be doable.  mixing in Scheme scripts might work
better in some situations (like unicode etc).

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!

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