Hi John, On Sat 21 May 2011 23:09, John Cowan <[email protected]> writes:
> Andy Wingo scripsit: > >> Right, control features. I already mentioned the >> multiple-return-from-mapping proc issue before. There are three >> options that I am aware of: >> >> 1) Ignore the issue. >> >> 2) Specify that a second return from a mapped procedure cannot >> affect the data structure returned by the first return. Effectively >> prohibits the build-it-backwards-and-reverse-in-place idiom, though >> you may reverse and form a new list. >> >> 3) Specify that it is an error to return multiple times. > > I have filed a ticke for choice 3. I don't see that anyone will want 2, > especially for string-map and vector-map. FWIW R6RS chose option 2, in a discussion in which you participated. Regarding vector-map: http://lists.r6rs.org/pipermail/r6rs-discuss/2007-June/002775.html (Not that long ago, right?) >> Suggestion: remove vector-map, string-map, and their for-each >> procedures from the WG1 report. > > The WG1 charter says: "Self consistency is an important objective, > which may require adding new features." I can quote too :) "A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines." Less polemically: consistency has a value, but for me it stops well before the useless "blob-map". Andy -- http://wingolog.org/ _______________________________________________ Scheme-reports mailing list [email protected] http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports
