Open larceny-trac-import opened 11 years ago
Author: pnkfelix Just wanted to record that Jesse and Felix met with Will on April 5th and talked about this, and I believe that we agreed:
The only questionable or ambiguous thing about the above description is whether leaving a parameterize form that affected current-directory should actually chdir back to the prior directory, rather than just leaving that job for later. This becomes an issue when such a chdir would signal an error (e.g. because the directory you want to chdir to no longer exists).
Jesse has argued that it could be very non-intuitive to have exiting a parameterize to raise an exception, which implies that we should not chdir on exit from a parameterize. This would mean that errors would not be signalled until something else does the chdir (or perhaps no error would ever be signalled).
Felix believes that if we made exiting the parameterize behave differently from entering it, then we can't get away with the simple implementation of parameterize that Jesse has suggested to Felix (where parameterize has no magic, it just treats parameters as procedures and all the continuation mark magic is handled by the parameter object itself). At the very least, it would mean that the interface between parameterize and the parameter objects would have to be extended to differentiate between the on-entry and on-exit cases.
(But Jesse and Felix have been talking about doing that anyway, to allow safe-for-space implementation of a current-larceny-root parameter coupled to a LARCENY_ROOT environment variable.)
_Reported by: tov on Wed Apr 5 16:58:24 2006 _ In particular: