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usage of various characters '[', ']', and ':'



I'm trying to figure out what special significance the characters '[',
']', and ':' have in Kawa

Kawa's handling of the colon character seems to violate R5RS, and thus
sticks out like a sore thumb for my work.  I can't currently support
handling the ":=" operator in the language I'm parsing because of
Kawa's handling of colon. 
Here are some example evaluations:

  (quote :=)		==>	=: 

  ':=asfda		==>	=asfda:

  (symbol? '=:)		==>	#f

All this of course is probably be considered perfectly valid, given
the description of Keywords in section 7.3 of the Kawa manual.  But I
would like a way to treat the colon in an R5RS compliant manner, even
if it were a command-line or environmental option to disable Keywords,
[which I don't use]

Another option (which is probably cleaner, in terms of overall design)
would be to make quotation a higher precedence operation on tokens
than keywordization (in other words, if I say ':asfdasasfsasa, I'm
saying I want a symbol, not a keyword).  Quote is a special form
anyway, so I don't believe that giving it this behavior is out of
line.

In any case, I got around the problem by hacking the code, breaking
keywords in the process, but I would like to see a real solution in
the main repository that still provided keyword support.

On the other topic, I haven't been able to discern what status '[' and
']' have been given in Kawa's Scheme system.  They seem to do
SOMETHING, but its unclear to me what it is.

	   [+ 2 3 ]	   ==>	 5
	   [+ 2 3]	   ==>  ...prompts for further input with
			        something like #|[---:100|# (I noticed
				its a '[' and not a '(', so obviously
				something special is going on) and
				when I do type some closing brackets,
				things break.

Is thips just some special casing of brackets to deal with array types,
and I am exploring dark dark terrain that I shouldn't be poking my
nose into? 

-Felix


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