William D Clinger scripsit: > Implementations of the R6RS may use variable-width > representations while achieving O(1) amortized time for > string-length, string-ref, and string-set!.
Indeed. What's more, there are four classes of programs: a) those which need O(1) read/write access to characters in strings; b) those which need O(1) read (but not write) access; c) those which need amortized O(1) access; d) those which do not need O(1) access at all. Alas, there is no knowing a priori which Scheme implementations will be used to execute which applications, so it's hard to make the appropriate tradeoffs in advance. -- John Cowan [EMAIL PROTECTED] http://ccil.org/~cowan The penguin geeks is happy / As under the waves they lark The closed-source geeks ain't happy / They sad cause they in the dark But geeks in the dark is lucky / They in for a worser treat One day when the Borg go belly-up / Guess who wind up on the street. _______________________________________________ r6rs-discuss mailing list [email protected] http://lists.r6rs.org/cgi-bin/mailman/listinfo/r6rs-discuss
