If we make `working-directory` and `umask` into R7RS-small-style parameters and get rid of the two setters, we don't have to decide between (b) or copying and (c) or sharing semantics. I think this is overall a win, which is precisely why R7RS-small does not specify (but does not prevent) setting as distinct from parameterization.
Comments?
(There seems to be no constituency for (a) semantics, which is creating a new parameter in the new thread and reinitializing it. As far as I know, only Scheme48 provides it.)
John Cowan http://vrici.lojban.org/~cowanxxxxxx@ccil.org Awk!" sed Grep. "A fscking python is perloining my Ruby; let me bash him with a Cshell! Vi didn't I mount it on a troff?" --Francis Turner