Implement print-circle, allowing recursive and circular structures to be read. src/ChangeLog addition: 2011-09-04 Aidan Kehoe <kehoea@parhasard.net> * alloc.c: * alloc.c (ALLOC_FROB_BLOCK_LISP_OBJECT_1): * alloc.c (ALLOC_FROB_BLOCK_LISP_OBJECT): * alloc.c (cons_print_preprocess): * alloc.c (vector_print_preprocess): * alloc.c (vector_nsubst_structures_descend): * alloc.c (Fmake_symbol): * alloc.c (UNMARK_symbol): * alloc.c (sweep_symbols): * alloc.c (reinit_alloc_objects_early): * alloc.c (reinit_alloc_early): * bytecode.c: * bytecode.c (compiled_function_print_preprocess): * bytecode.c (compiled_function_nsubst_structures_descend): * bytecode.c (set_compiled_function_arglist): * bytecode.c (set_compiled_function_interactive): * bytecode.c (bytecode_objects_create): * chartab.c: * chartab.c (print_preprocess_mapper): * chartab.c (nsubst_structures_mapper): * chartab.c (char_table_nsubst_structures_descend): * chartab.c (chartab_objects_create): * elhash.c: * elhash.c (nsubst_structures_map_hash_table): * elhash.c (hash_table_nsubst_structures_descend): * elhash.c (print_preprocess_mapper): * elhash.c (hash_table_print_preprocess): * elhash.c (inchash_eq): * elhash.c (hash_table_objects_create): * elhash.c (syms_of_elhash): * elhash.h: * emacs.c (main_1): * fns.c: * fns.c (check_eq_nokey): * fns.c (Fnsubst): * fns.c (syms_of_fns): * lisp.h: * lisp.h (struct Lisp_Symbol): * lisp.h (IN_OBARRAY): * lisp.h (struct): * lisp.h (PRINT_PREPROCESS): * lread.c (read1): * lrecord.h: * lrecord.h (struct lrecord_implementation): * lrecord.h (DEFINE_DUMPABLE_MODULE_LISP_OBJECT): * print.c: * print.c (PRINT_CIRCLE_LIMIT): * print.c (print_continuous_numbering_changed): * print.c (print_prepare): * print.c (print_finish): * print.c (Fprin1_to_string): * print.c (print_cons): * print.c (print_preprocess_inchash_eq): * print.c (print_preprocess): * print.c (print_sort_get_numbers): * print.c (print_sort_compare_ordinals): * print.c (print_gensym_or_circle): * print.c (nsubst_structures_descend): * print.c (nsubst_structures): * print.c (print_internal): * print.c (print_symbol): * print.c (vars_of_print): * rangetab.c: * rangetab.c (range_table_print_preprocess): * rangetab.c (range_table_nsubst_structures_descend): * rangetab.c (rangetab_objects_create): * rangetab.c (syms_of_rangetab): * symbols.c: * symbols.c (symbol_print_preprocess): * symbols.c (Fintern): * symbols.c (Funintern): * symbols.c (reinit_symbol_objects_early): * symbols.c (init_symbols_once_early): * symsinit.h: Implement print-circle, printing circular structures in a readable fashion, and treating them appropriately on read. This is by means of two new object methods, print_preprocess (detecting circularities), and nsubst_structures_descend (replacing placeholders with the read objects). Expose the substitution to Lisp via #'nsubst and its new :descend-structures keyword. Store information as to whether symbols are interned in obarray or not in their header, making checking for keywords and uninterned symbols (and thus printing) cheaper. Default print_gensym to t, as Common Lisp does, and as a more-than-decade old comment suggests. lisp/ChangeLog addition: 2011-09-04 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el (byte-compile-output-file-form): * bytecomp.el (byte-compile-output-docform): Bind print-circle, print-continuous-numbering in these functions, now those variables are available. * lisp.el (forward-sexp): * lisp.el (backward-sexp): Recognise leading #N= as being part of an expression. tests/ChangeLog addition: 2011-09-04 Aidan Kehoe <kehoea@parhasard.net> * automated/lisp-reader-tests.el: * automated/lisp-tests.el (literal-with-uninterned): * automated/symbol-tests.el (foo): Test print-circle, for printing (mutually-)recursive and circular structures. Bind print-continuous-numbering where appropriate.

: #-*- Perl -*-
eval 'exec perl -w -S $0 ${1+"$@"}' # Portability kludge
    if 0;

# config.values.sh --- create config.values.in from ../configure

# Copyright (C) 1997, 1999 Martin Buchholz

# Author:	Martin Buchholz
# Maintainer:	Martin Buchholz
# Keywords:	configure elisp report-xemacs-bugs

# This file is part of XEmacs.
# 
# XEmacs is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation, either version 3 of the License, or (at your
# option) any later version.
# 
# XEmacs is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# for more details.
# 
# You should have received a copy of the GNU General Public License
# along with XEmacs.  If not, see <http://www.gnu.org/licenses/>.

### Commentary:

## Extract all the @foo@ configuration symbols from ../configure
## to make them available to elisp later (see util/config.el)
## Primarily useful for creating ridiculously verbose bug reports.
##
## See lisp/config.el, ../configure.in,
## and the Autoconf documentation on AC_OUTPUT, for more details.
##
## This script needs only to be run occasionally (before a Net release)
## by an XEmacs Maintainer (consider yourself so blessed, if you are
## actually reading this commentary).
##

if (! -r "./configure") {
  chdir ".." or die "Can't chdir: $!";
  if (! -r "./configure") {
    die "Can't find configure!";
  }
}

sub FileContents {
  local $/ = undef; # Slurp mode
  open (FILE, "< $_[0]") or die "$_[0]: $!";
  my $contents = <FILE>;
  close FILE or die "$_[0]: $!";
  return $contents;
}

my $configure_contents = FileContents "./configure";
my $cvi_contents = FileContents "lib-src/config.values.in";

my $new_cvi_contents =
";;; Do not edit this file!
;;; This file was automatically generated, by the config.values.sh script,
;;; from configure, which was itself automatically generated from configure.in.
;;;
;;; See lisp/config.el for details on how this file is used.
;;;
;;; You are trapped in a twisty maze of strange-looking files, all autogenerated...

;;; configure        is created, from configure.in,     by autoconf
;;; config.values.in is created, from configure,        by config.values.sh
;;; config.values    is created, from config.values.in, by configure
;;; config.values    is read by lisp/config.el,
;;;                  to create the (Lisp object) config-value-hash-table

;;; Variables defined in configure by AC_SUBST follow:
;;; (These are used in Makefiles)

";

my %done;
for my $var (sort { $a cmp $b }
	     $configure_contents =~
	     /^s\,\@([A-Za-z0-9_]+)\@\,\$[A-Za-z0-9_]+\,;t t/mg) {
  $new_cvi_contents .= "$var \"\@$var\@\"\n" unless exists $done{$var};
  $done{$var} = 1;
}

$new_cvi_contents .= "
;;; Variables defined in configure by AC_DEFINE and AC_DEFINE_UNQUOTED follow:
;;; (These are used in C code)

";

if ($cvi_contents ne $new_cvi_contents) {
  unlink "lib-src/config.values.in";
  open (CVI, "> lib-src/config.values.in")
    or die "lib-src/config.values.in: $!";
  print CVI $new_cvi_contents;
  close CVI
    or die "lib-src/config.values.in: $!";
}