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Re: Octet vs Char (Re: strings draft)

This page is part of the web mail archives of SRFI 50 from before July 7th, 2015. The new archives for SRFI 50 contain all messages, not just those from before July 7th, 2015.

From my understanding there are a few issues being discussed here
(with possibly overlapping consequences) -- O(1) performance of
strings and using strings for octet sequences.

SRFI-4 defines homogenous numeric vectors which seem like they would
suffice for implementing octet streams independant of strings and, if
not, a few Scheme implementations (larceny, MIT/GNU-scheme) provide

As for O(1) performance, there's undoubtably a need for
non-O(1)-string-like-heavy-weight-objects (herein called ropes) which
some implementations choose to implement and call them strings (as
permitted by r5rs).  The current proposal seems to urge
implementations to provide these as a seperate data type.

Two reasons for this distinction seem to be:

  ~ efficiency

    Carrying around the full weight of a rope for all strings might be
    too excessive, but then r5rs doesn't define the concept of a
    fixnum which most implementations utilize to avoid needing to
    provide heap allocated bignums.

  ~ use in binary I/O

    relating back to the discussion above -- should an alternative
    idiom be employed for this rather than reusing strings for this