🚀 go-pugleaf

About consts in container classes: Yes, many of the classes have not
yet been const-ified, mostly just out of time constraints. Sorry.
Also, a bunch of things should ideally be rewritten, rather than
patched, to support const for containers. But just patching them in
would probably be serviceable. (As with any new C++ feature, an
implementation written from scratch given the feature is almost always
better than one with the feature patched in, but patching is a lot
better than nothing!)

If you or anyone else would like to volunteer to place member consts
in the Plex and/or other pseudogeneric class files, this would be very
helpful. I would happily review your changes and integrate them into
a libg++ release.

(Another snag about all this is that in gcc and g++, `const' as an
ordinary function qualifier is supported to mean that the function is
a `pure' function, i.e., that repeated applications of the function
with the same arguments always return the same results, with no side
effects.  Specifying this kind of const allows the backend to perform
some powerful optimizations that are not possible with the C++ const
construct, since C++ const doesn't promise complete lack of side
effects. Ideally, many functions should be revised/relabelled to
support this as well, although there are two obstacles: The usage is
not C++ 2.0 or ANSI C standard, and the backend does not (yet?) know
how to handle gnu-const functions with pointer arguments, which
includes all member functions, since `this' is implicitly an argument
to member functions.)


The Vec.ccP problem you mention appears to be a real g++ limitation:
It seems to be complaining because temporary vars are created in the
jumped-over part that g++ apparently doesn't see are killable before
jump_over: so it thinks that the binding context is different. I'll
revise this code a bit to work around this limitation, via:

*** Vec.ccP~	Mon Aug 21 07:07:03 1989
--- Vec.ccP	Tue Feb  6 06:19:56 1990
***************
*** 312,321 ****
                  SWAP (mid, lo);
                if ((*cmp) (*hi, *mid) < 0)
                  SWAP (mid, hi);
!               else 
!                 goto jump_over;
!               if ((*cmp) (*mid, *lo) < 0)
!                 SWAP (mid, lo);
!             jump_over:
                *pivot = *mid;
                pivot = &pivot_buffer;
--- 312,320 ----
                  SWAP (mid, lo);
                if ((*cmp) (*hi, *mid) < 0)
+               {
                  SWAP (mid, hi);
!                 if ((*cmp) (*mid, *lo) < 0)
!                   SWAP (mid, lo);
!               }
                *pivot = *mid;
                pivot = &pivot_buffer;

 

>   Also, Doug, the Reply-To address in the mail you sent me didn't
> work.  UUCP or whatever-it-was has always been magic to me anyway:
 
If you have uucp connects, you ought to be able to reply via some
path like that below if you know how to get to rutgers or cornell.

Doug Lea, Computer Science Dept., SUNY Oswego, Oswego, NY, 13126 (315)341-2367
email: dl@oswego.edu              or dl%oswego.edu@nisc.nyser.net
UUCP :...cornell!devvax!oswego!dl or ...rutgers!sunybcs!oswego!dl