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reading, escapism, and astrology



	My questions about escape sequences in strings was motivated by
attempting to get the test cases in Oleg Kiselyov's SSAX parser to work.
After spending far too long mindlessly typing in format statements, making
the excuse that I should look at the code and the tests anyway, I decided
that I should really do this task automatically. Thinking that there had to be
a complete functioning scheme reader somewhere in all of the DrScheme code
(there is) I decided that I would mangle it to emit a modified version of the
code.  Suddenly a light came on, and I thought that since DrScheme switches
languages, it should be possible to switch readers.
	I think it is possible to switch readers, maybe even easy to
do so.  I do have a few questions.  

One: There appear to be two readers, one a raw reader, and the other a
zodiac reader.  It appears that the raw reader is only called when one
is in either MzScheme or MrEd non debug modes, but I am less than
certain of that.  Is that true?  Experiment has shown that mangling
the zodiac scanner makes a reader which seems to work nicely in MrEd
debug mode.  (Cringe if you must, I do promise not to inflict my
experiments on anyone but myself until I have at least a vague idea of
what I am doing.  

Two: It appears that the readers are parameters, but are they settable
from the outside of DrScheme?  If not (as I suspect), what would be
the archiecturaly soundest way to add a new language that has and
improved scaqnner?

Three: I am not completely understanding how zodiac gets linked and inserted
into DrScheme.  All I really need is to make a new unit with the signature
of zodiac-scanner-code^ and relink everything, but I'm not even going to try
anything like that until I have something like a rented clue.

	Thanks,
		Deinst