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explicit quoting/unquoting of strings

The SRFI specifies an escape mechanism for expressing strings in a
reduced character set (Section "Quoted strings").

It would substantially increase portability and convenience if the quoting
and unquoting mechanism is also made available explicitly to application
programs---for example through procedures like this:

(string-quote str)
        produces a representation of string str in the reduced set of characters
        <<specify here>> by introducing backslash escape sequences.
        The result is a newly allocated string s satisfying
                (string=? (string-unquote s) str)

(string-unquote str [ state ] ) -> str' state'
        interprets backslash escape sequences in string str and constructs the
        string being represented.
            The optional argument state, and the second return value state',
        represent the state of the interpreter (a finite state machine) before and
        after processing str. By passing the state from one invokation of
        string-unquote to the next, it is possible to unquote arbitrary substrings
        of a stream of characters---even if the stream is broken within escape
        sequences. The state #f (default for state) is the start state (taking letters
        etc. at face value.) Other states are <<specify?; need to know?; ints?>>.

Dr. Sebastian Egner
Senior Scientist
Philips Research Laboratories
Prof. Holstlaan 4 (WDC 1-051, 1st floor, room 51)
5656 AA Eindhoven
The Netherlands
tel:       +31 40 27-43166
fax:      +31 40 27-44004
email: sebastian.egner@xxxxxxxxxxx