Per Bothner scripsit: > The scheme-report-environment and null-environment function take > a version number - but only 5 is specified. That seems strange. > Specifically, version 7 does not need to be supported.
Correct, as these procedures exist only in the (scheme r5rs) library. It's not even clear what they would mean with an argument of 7; see below. > Perhaps an editorial note that these routines are only for > compatibility with R6RS and not recommended for new code? R5RS, rather. That's why they're only in that library, just as in R6RS they were only in the (rnrs r5rs) library (and only required 5). > Perhaps it makes sense to add a note that > (scheme-report-environment 5) > is equivalent to > (environment '(scheme r5rs)) That's just what the description says, in prose rather than Scheme. > Non-editorial: Should one define > (scheme-report-environment 7) > perhaps as: > (environment '(scheme all)) There is no such library. We discussed it, but the WG consensus was that it didn't make sense: you only know what's in it if you know exactly which underlying libraries your implementation provides. In R6RS all libraries are mandatory, so it's not an issue. It's already a problem that you don't necessarily know what's in the (scheme r5rs) library: if you don't have (scheme read), your R5RS library probably doesn't have `read` either. > This part is non-editorial - should there be a library > corresponding to: > (null-environment 5) > Perhaps: > (environment '(scheme r5rs null)) I think the null environment is an anachronism. It made some sense in the R4RS context, which had neither `eval` nor environments, but planned to add them, and the syntactic keywords were a fixed list. But syntactic and variable identifiers are mostly on a par nowadays, and what's the point of a library having one but not the other? If you've used it in anger, I'd like to hear about it. -- John Cowan [email protected] http://ccil.org/~cowan This great college [Trinity], of this ancient university [Cambridge], has seen some strange sights. It has seen Wordsworth drunk and Porson sober. And here am I, a better poet than Porson, and a better scholar than Wordsworth, somewhere betwixt and between. --A.E. Housman _______________________________________________ Scheme-reports mailing list [email protected] http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports
