From: John Cowan <[EMAIL PROTECTED]> Subject: Re: [r6rs-discuss] Unicode issues Date: Tue, 28 Aug 2007 15:22:33 -0400
> 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. True. I'd rather cound on higher-level string/text srfis which allows implementations to provide optimized high-level string operations, bypassing index-based access. --shiro _______________________________________________ r6rs-discuss mailing list [email protected] http://lists.r6rs.org/cgi-bin/mailman/listinfo/r6rs-discuss
