srcprop.h, tags.h, throw.c, unif.c: Added new selectors
SCM_SETAND_CAR, SCM_SETAND_CDR, SCM_SETOR_CAR and SCM_SETOR_CDR.
Motivation: Safer use. Some other macros are defined in terms of
these operations. If these are defined using the SCM_SETCXR
(<e1>, SCM_CXR (<e1>) <op> <e2>) pattern a complex <e1> will lead
to inefficiency and an <e1> with side-effects could potentially
break. Also, these particular operations are heavily utilized in
the garbage collector. In unoptimized code there will be a
measurable speedup.
* alist.c, arbiters.c, continuations.c, debug.c, debug.h, eval.c,
eval.h, feature.c, filesys.c, fports.c, gc.c, gsubr.c, init.c,
ioext.c, kw.c, list.c, load.c, mallocs.c, numbers.c, numbers.h,
pairs.c, pairs.h, ports.c, ports.h, posix.c, procprop.c, procs.c,
procs.h, ramap.c, read.c, root.c, srcprop.c, srcprop.h,
strports.c, symbols.c, tags.h, throw.c, unif.c, variable.c,
vports.c: Cleaned up use of pairs: Don't make any special
assumptions about the internal structure of selectors and
mutators: SCM_CXR (<e1>) = <e2> --> SCM_SETCXR (<e1>, <e2>),
SCM_CXR (<e1>) &= <e2> --> SCM_SETAND_CXR (<e1>, <e2>) etc.
(Among other things, this change makes it easier to build Guile
with certain compilers which have problems with casted lvalues.)
wta for range errors (ASSERT still needs work).
* error.c, error.h (scm_out_of_range): new procedure.
* error.c, error.h (scm_out_of_range_key): new key.
* posix.c (scm_sync): #else was missing.
* error.c, error.h: append _key to names scm_num_overflow and
scm_system_error.
* __scm.h (SCM_SYSMISSING, SCM_NUM_OVERFLOW): use SCM_BOOL_F instead
of consing an empty list.
(SCM_SYSERROR etc.): move into error.c, make them procedures instead
of macros, saves code and string space.
error.c, fports.c, numbers.c, posix.c, ioext.c, filesys.c, socket.c,
fdsocket.c, simpos.c: change names of SCM_SYSERROR etc., to
lower case. Rename scm_syserror_m to scm_syserror_msg.
error.h: prototypes for new procedures.
symbols, when defining the scheme values R_OK, W_OK, X_OK, and F_OK.
The symbols aren't available on some systems, and I'm pretty sure
their values are fixed by common widespread practice.
* ioext.c (scm_init_ioext): Code here defined them too; remove it.
