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// GNU Guix --- Functional package management for GNU
// Copyright © 2016 Ricardo Wurmus <rekado@elephly.net>
//
// This file is part of GNU Guix.
//
// GNU Guix 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.
//
// GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

var outerRadius = Math.max(nodeArray.length * 15, 500) / 2,
    innerRadius = outerRadius - Math.min(nodeArray.length * 5, 200),
    width = outerRadius * 2,
    height = outerRadius * 2,
    colors = d3.scale.category20c(),
    matrix = [];

function neighborsOf (node) {
    return links.filter(function (e) {
        return e.source === node;
    }).map(function (e) {
       return e.target;
    });
}

function zoomed () {
    zoomer.attr("transform",
                "translate(" + d3.event.translate + ")" +
                "scale(" + d3.event.scale + ")");
}

function fade (opacity, root) {
    return function (g, i) {
        root.selectAll("g path.chord")
            .filter(function (d) {
                return d.source.index != i && d.target.index != i;
            })
            .transition()
            .style("opacity", opacity);
    };
}

// Now that we have all nodes in an object we can replace each reference
// with the actual node object.
links.forEach(function (link) {
  link.target = nodes[link.target];
  link.source = nodes[link.source];
});

// Construct a square matrix for package dependencies
nodeArray.forEach(function (d, index, arr) {
    var source = index,
        row = matrix[source];
    if (!row) {
        row = matrix[source] = [];
        for (var i = -1; ++i < arr.length;) row[i] = 0;
    }
    neighborsOf(d).forEach(function (d) { row[d.index]++; });
});

// chord layout
var chord = d3.layout.chord()
    .padding(0.01)
    .sortSubgroups(d3.descending)
    .sortChords(d3.descending)
    .matrix(matrix);

var arc = d3.svg.arc()
    .innerRadius(innerRadius)
    .outerRadius(innerRadius + 20);

var zoom = d3.behavior.zoom()
    .scaleExtent([0.1, 10])
    .on("zoom", zoomed);

var svg = d3.select("body").append("svg")
    .attr("width", "100%")
    .attr("height", "100%")
    .attr('viewBox', '0 0 ' + Math.min(width, height) + ' ' + Math.min(width, height))
    .attr('preserveAspectRatio', 'xMinYMin')
    .call(zoom);

var zoomer = svg.append("g");

var container = zoomer.append("g")
    .attr("transform", "translate(" + outerRadius + "," + outerRadius + ")");

// Group for arcs and labels
var g = container.selectAll(".group")
    .data(chord.groups)
    .enter().append("g")
    .attr("class", "group")
    .on("mouseout", fade(1, container))
    .on("mouseover", fade(0.1, container));

// Draw one segment per package
g.append("path")
    .style("fill",   function (d) { return colors(d.index); })
    .style("stroke", function (d) { return colors(d.index); })
    .attr("d", arc);

// Add circular labels
g.append("text")
    .each(function (d) { d.angle = (d.startAngle + d.endAngle) / 2; })
    .attr("dy", ".35em")
    .attr("transform", function (d) {
      return "rotate(" + (d.angle * 180 / Math.PI - 90) + ")"
          + "translate(" + (innerRadius + 26) + ")"
          + (d.angle > Math.PI ? "rotate(180)" : "");
    })
    .style("text-anchor", function (d) { return d.angle > Math.PI ? "end" : null; })
    .text(function (d) { return nodeArray[d.index].label; });

// Draw chords from source to target; color by source.
container.selectAll(".chord")
    .data(chord.chords)
    .enter().append("path")
    .attr("class", "chord")
    .style("stroke", function (d) { return d3.rgb(colors(d.source.index)).darker(); })
    .style("fill", function (d) { return colors(d.source.index); })
    .attr("d", d3.svg.chord().radius(innerRadius));
f='#n263'>263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447
dnl GNU Guix --- Functional package management for GNU
dnl Copyright © 2012, 2013, 2014, 2015, 2016, 2018, 2019, 2020, 2021 Ludovic Courtès <ludo@gnu.org>
dnl Copyright © 2014 Mark H Weaver <mhw@netris.org>
dnl Copyright © 2017 Efraim Flashner <efraim@flashner.co.il>
dnl Copyright © 2021 Chris Marusich <cmmarusich@gmail.com>
dnl
dnl This file is part of GNU Guix.
dnl
dnl GNU Guix is free software; you can redistribute it and/or modify it
dnl under the terms of the GNU General Public License as published by
dnl the Free Software Foundation; either version 3 of the License, or (at
dnl your option) any later version.
dnl
dnl GNU Guix is distributed in the hope that it will be useful, but
dnl WITHOUT ANY WARRANTY; without even the implied warranty of
dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
dnl GNU General Public License for more details.
dnl
dnl You should have received a copy of the GNU General Public License
dnl along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

dnl GUIX_SYSTEM_TYPE
dnl
dnl Determine the Guix host system type, and store it in the
dnl `guix_system' variable.
AC_DEFUN([GUIX_SYSTEM_TYPE], [
  AC_REQUIRE([AC_CANONICAL_HOST])
  AC_PATH_PROG([SED], [sed])

  AC_ARG_WITH(system, AS_HELP_STRING([--with-system=SYSTEM],
    [Platform identifier (e.g., `i686-linux').]),
    [guix_system="$withval"],
    [case "$host_cpu" in
       i*86)
	  machine_name="i686";;
       amd64)
          machine_name="x86_64";;
       arm|armv[[7-9]]*)
          # Here we want to exclude CPUs such as "armv6l".  On ARMv7
          # machines, we normally get "armv7l".  However, in Guix, we
          # configure with --build=arm-unknown-linux-gnueabihf, leading
          # to just "arm", so we also have to allow it.
          #
          # TODO: If not cross-compiling, add a sanity check to make
          #       sure this build machine has the needed features to
          #       support executables compiled using our armhf gcc,
          #       configured with:
          #         --with-arch=armv7-a
          #         --with-float=hard
          #         --with-mode=thumb
          #         --with-fpu=vfpv3-d16
	  machine_name="armhf";;
       *)
	  machine_name="$host_cpu";;
     esac

     case "$host_os" in
       linux-gnu*)
	  # For backward compatibility, strip the `-gnu' part.
	  guix_system="$machine_name-linux";;
       gnu*)
          # Always use i586 for GNU/Hurd.
          guix_system="i586-gnu";;
       *)
	  # Strip the version number from names such as `gnu0.3',
	  # `darwin10.2.0', etc.
	  guix_system="$machine_name-`echo $host_os | "$SED" -e's/[0-9.]*$//g'`";;
     esac])

  AC_MSG_CHECKING([for the Guix system type])
  AC_MSG_RESULT([$guix_system])

  AC_SUBST([guix_system])
])

dnl GUIX_ASSERT_SUPPORTED_SYSTEM
dnl
dnl Assert that this is a system to which the distro is ported.
AC_DEFUN([GUIX_ASSERT_SUPPORTED_SYSTEM], [
  AC_REQUIRE([GUIX_SYSTEM_TYPE])

  AC_ARG_WITH([courage], [AS_HELP_STRING([--with-courage],
    [Assert that even if this platform is unsupported, you will be
courageous and port the GNU System distribution to it (see
"GNU Distribution" in the manual.)])],
    [guix_courageous="$withval"],
    [guix_courageous="no"])

  # Currently only Linux-based systems are supported, and only on some
  # platforms.
  case "$guix_system" in
    x86_64-linux|i686-linux|armhf-linux|aarch64-linux|powerpc64le-linux)
      ;;
    *)
      if test "x$guix_courageous" = "xyes"; then
        AC_MSG_WARN([building Guix on `$guix_system', which is not supported])
      else
        AC_MSG_ERROR([`$guix_system' is not a supported platform.
See "GNU Distribution" in the manual, or try `--with-courage'.])
      fi
      ;;
  esac
])

dnl GUIX_ASSERT_GUILE_FEATURES FEATURES
dnl
dnl Assert that FEATURES are provided by $GUILE.
AC_DEFUN([GUIX_ASSERT_GUILE_FEATURES], [
  for guix_guile_feature in $1
  do
    AC_MSG_CHECKING([whether $GUILE provides feature '$guix_guile_feature'])
    if "$GUILE" -c "(exit (provided? '$guix_guile_feature))"
    then
      AC_MSG_RESULT([yes])
    else
      AC_MSG_RESULT([no])
      AC_MSG_ERROR([$GUILE does not support feature '$guix_guile_feature', which is required.])
    fi
  done
])

dnl GUIX_CHECK_GUILE_SSH
dnl
dnl Check whether a recent-enough Guile-SSH is available.
AC_DEFUN([GUIX_CHECK_GUILE_SSH], [
  dnl Check whether '#:nodelay' paramater to 'make-session' (introduced in
  dnl 0.13.0) is present.
  AC_CACHE_CHECK([whether Guile-SSH is available and recent enough],
    [guix_cv_have_recent_guile_ssh],
    [GUILE_CHECK([retval],
      [(and (@ (ssh channel) channel-send-eof)
            (@ (ssh popen) open-remote-pipe)
            (@ (ssh dist node) node-eval)
            (@ (ssh auth) userauth-gssapi!)
            ((@ (ssh session) make-session) #:nodelay #t))])
     if test "$retval" = 0; then
       guix_cv_have_recent_guile_ssh="yes"
     else
       guix_cv_have_recent_guile_ssh="no"
     fi])
])

dnl GUIX_CHECK_GUILE_SQLITE3
dnl
dnl Check whether a recent-enough Guile-Sqlite3 is available.
AC_DEFUN([GUIX_CHECK_GUILE_SQLITE3], [
  dnl Check whether 'sqlite-bind-arguments' is available.  It was introduced
  dnl in February 2018:
  dnl <https://notabug.org/guile-sqlite3/guile-sqlite3/commit/1cd1dec96a9999db48c0ff45bab907efc637247f>.
  AC_CACHE_CHECK([whether Guile-Sqlite3 is available and recent enough],
    [guix_cv_have_recent_guile_sqlite3],
    [GUILE_CHECK([retval],
      [(@ (sqlite3) sqlite-bind-arguments)])
     if test "$retval" = 0; then
       guix_cv_have_recent_guile_sqlite3="yes"
     else
       guix_cv_have_recent_guile_sqlite3="no"
     fi])
])

dnl GUIX_CHECK_GUILE_JSON
dnl
dnl Check whether a recent-enough Guile-JSON is available.
AC_DEFUN([GUIX_CHECK_GUILE_JSON], [
  dnl Check whether we're using Guile-JSON 4.3+, which provides
  dnl 'define-json-mapping'.
  AC_CACHE_CHECK([whether Guile-JSON is available and recent enough],
    [guix_cv_have_recent_guile_json],
    [GUILE_CHECK([retval],
      [(use-modules (json))

       (define-json-mapping <frob> make-frob
         frob?
	 json->frob
	 (a frob-a)
	 (b frob-b \"bee\"))

       (exit
        (equal? (json->frob
                 (open-input-string \"{ \\\"a\\\": 1, \\\"bee\\\": 2 }\"))
                (make-frob 1 2)))])
     if test "$retval" = 0; then
       guix_cv_have_recent_guile_json="yes"
     else
       guix_cv_have_recent_guile_json="no"
     fi])
])

dnl GUIX_CHECK_GUILE_GCRYPT
dnl
dnl Check whether a recent-enough Guile-Gcrypt is available.
AC_DEFUN([GUIX_CHECK_GUILE_GCRYPT], [
  dnl Check whether we're using Guile-Gcrypt 0.2.x or later.  0.2.0
  dnl introduced the 'hash-algorithm' macro and related code.
  AC_CACHE_CHECK([whether Guile-Gcrypt is available and recent enough],
    [guix_cv_have_recent_guile_gcrypt],
    [GUILE_CHECK([retval],
      [(use-modules (gcrypt hash))
       (equal? (hash-algorithm sha256)
               (lookup-hash-algorithm 'sha256))])
     if test "$retval" = 0; then
       guix_cv_have_recent_guile_gcrypt="yes"
     else
       guix_cv_have_recent_guile_gcrypt="no"
     fi])
])

dnl GUIX_CHECK_GUILE_GIT
dnl
dnl Check whether a recent-enough Guile-Git is available.
AC_DEFUN([GUIX_CHECK_GUILE_GIT], [
  dnl Check whether we're using Guile-Git 0.3.0 or later.  0.3.0
  dnl introduced SSH authentication support and more.
  AC_CACHE_CHECK([whether Guile-Git is available and recent enough],
    [guix_cv_have_recent_guile_git],
    [GUILE_CHECK([retval],
      [(use-modules (git) (git auth) (git submodule))
       (let ((auth (%make-auth-ssh-agent)))
         repository-close!
	 object-lookup-prefix
         (make-clone-options
          #:fetch-options (make-fetch-options auth)))])
     if test "$retval" = 0; then
       guix_cv_have_recent_guile_git="yes"
     else
       guix_cv_have_recent_guile_git="no"
     fi])
])

dnl GUIX_CHECK_GUILE_ZLIB
dnl
dnl Check whether a recent-enough Guile-zlib is available.
AC_DEFUN([GUIX_CHECK_GUILE_ZLIB], [
  dnl Check whether we're using Guile-zlib 0.1.0 or later.
  dnl 0.1.0 introduced the 'make-zlib-input-port' and related code.
  AC_CACHE_CHECK([whether Guile-zlib is available and recent enough],
    [guix_cv_have_recent_guile_zlib],
    [GUILE_CHECK([retval],
      [(use-modules (zlib))
       make-zlib-input-port])
     if test "$retval" = 0; then
       guix_cv_have_recent_guile_zlib="yes"
     else
       guix_cv_have_recent_guile_zlib="no"
     fi])
])

dnl GUIX_TEST_ROOT_DIRECTORY
AC_DEFUN([GUIX_TEST_ROOT_DIRECTORY], [
  AC_CACHE_CHECK([for unit test root directory],
    [ac_cv_guix_test_root],
    [ac_cv_guix_test_root="`pwd`/test-tmp"])
])

dnl 'BINPRM_BUF_SIZE' constant in Linux (we leave room for the trailing zero.)
dnl The Hurd has a limit of about a page (see exec/hashexec.c.)
m4_define([LINUX_HASH_BANG_LIMIT], 127)

dnl Hardcoded 'sun_path' length in <sys/un.h>.
m4_define([SOCKET_FILE_NAME_LIMIT], 108)

dnl GUIX_SOCKET_FILE_NAME_LENGTH
AC_DEFUN([GUIX_SOCKET_FILE_NAME_LENGTH], [
  AC_CACHE_CHECK([the length of the installed socket file name],
    [ac_cv_guix_socket_file_name_length],
    [ac_cv_guix_socket_file_name_length="`echo -n "$guix_localstatedir/guix/daemon-socket/socket" | wc -c`"])
])

dnl GUIX_TEST_SOCKET_FILE_NAME_LENGTH
AC_DEFUN([GUIX_TEST_SOCKET_FILE_NAME_LENGTH], [
  AC_REQUIRE([GUIX_TEST_ROOT_DIRECTORY])
  AC_CACHE_CHECK([the length of the socket file name used in tests],
    [ac_cv_guix_test_socket_file_name_length],
    [ac_cv_guix_test_socket_file_name_length="`echo -n "$ac_cv_guix_test_root/var/123456/daemon-socket/socket" | wc -c`"])
])

dnl GUIX_HASH_BANG_LENGTH
AC_DEFUN([GUIX_HASH_BANG_LENGTH], [
  AC_CACHE_CHECK([the length of a typical hash bang line],
    [ac_cv_guix_hash_bang_length],
    [ac_cv_guix_hash_bang_length=`echo -n "$storedir/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa-bootstrap-binaries-0/bin/bash" | wc -c`])
])

dnl GUIX_TEST_HASH_BANG_LENGTH
AC_DEFUN([GUIX_TEST_HASH_BANG_LENGTH], [
  AC_REQUIRE([GUIX_TEST_ROOT_DIRECTORY])
  AC_CACHE_CHECK([the length of a hash bang line used in tests],
    [ac_cv_guix_test_hash_bang_length],
    [ac_cv_guix_test_hash_bang_length=`echo -n "$ac_cv_guix_test_root/store/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa-bootstrap-binaries-0/bin/bash" | wc -c`])
])

dnl GUIX_CHECK_FILE_NAME_LIMITS
dnl
dnl GNU/Linux has a couple of silly limits that we can easily run into.
dnl Make sure everything is fine with the current settings.  Set $1 to
dnl 'yes' if tests can run, 'no' otherwise.
AC_DEFUN([GUIX_CHECK_FILE_NAME_LIMITS], [
  AC_REQUIRE([GUIX_SOCKET_FILE_NAME_LENGTH])
  AC_REQUIRE([GUIX_TEST_SOCKET_FILE_NAME_LENGTH])
  AC_REQUIRE([GUIX_HASH_BANG_LENGTH])
  AC_REQUIRE([GUIX_TEST_HASH_BANG_LENGTH])

  if test "$ac_cv_guix_socket_file_name_length" -ge ]SOCKET_FILE_NAME_LIMIT[; then
    AC_MSG_ERROR([socket file name would exceed the maxium allowed length])
  fi
  if test "$ac_cv_guix_test_socket_file_name_length" -ge ]SOCKET_FILE_NAME_LIMIT[; then
    AC_MSG_WARN([socket file name limit may be exceeded when running tests])
  fi

  $1=yes
  if test "$ac_cv_guix_hash_bang_length" -ge ]LINUX_HASH_BANG_LIMIT[; then
    $1=no
    AC_MSG_ERROR([store directory '$storedir' would lead to overly long hash-bang lines])
  fi
  if test "$ac_cv_guix_test_hash_bang_length" -ge ]LINUX_HASH_BANG_LIMIT[; then
    $1=no
    AC_MSG_WARN([test directory '$ac_cv_guix_test_root' may lead to overly long hash-bang lines])
  fi
])

dnl GUIX_CHECK_CXX11
dnl
dnl Check whether the C++ compiler can compile a typical C++11 program.
AC_DEFUN([GUIX_CHECK_CXX11], [
  AC_REQUIRE([AC_PROG_CXX])
  AC_CACHE_CHECK([whether $CXX supports C++11],
    [ac_cv_guix_cxx11_support],
    [save_CXXFLAGS="$CXXFLAGS"
     CXXFLAGS="-std=c++11 $CXXFLAGS"
     AC_COMPILE_IFELSE([
      AC_LANG_SOURCE([
	#include <functional>

	std::function<int(int)>
	return_plus_lambda (int x)
	{
	  auto result = [[&]](int y) {
	    return x + y;
	  };

	  return result;
	}
      ])],
      [ac_cv_guix_cxx11_support=yes],
      [ac_cv_guix_cxx11_support=no])
    CXXFLAGS="$save_CXXFLAGS"
  ])
])

dnl GUIX_ASSERT_CXX11
dnl
dnl Error out if the C++ compiler cannot compile C++11 code.
AC_DEFUN([GUIX_ASSERT_CXX11], [
  GUIX_CHECK_CXX11
  if test "x$ac_cv_guix_cxx11_support" != "xyes"; then
    AC_MSG_ERROR([C++ compiler '$CXX' does not support the C++11 standard])
  fi
])

dnl GUIX_LIBGCRYPT_LIBDIR VAR
dnl
dnl Attempt to determine libgcrypt's LIBDIR; store the result in VAR.
AC_DEFUN([GUIX_LIBGCRYPT_LIBDIR], [
  AC_PATH_PROG([LIBGCRYPT_CONFIG], [libgcrypt-config])
  AC_CACHE_CHECK([libgcrypt's library directory],
    [guix_cv_libgcrypt_libdir],
    [if test "x$LIBGCRYPT_CONFIG" != "x"; then
       guix_cv_libgcrypt_libdir=`$LIBGCRYPT_CONFIG --libs | grep -e -L | sed -e "s/.*-L\([[^ ]]\+\)[[[:blank:]]]\+-lgcrypt.*/\1/g"`
     else
       guix_cv_libgcrypt_libdir=""
     fi])
  $1="$guix_cv_libgcrypt_libdir"
])

dnl GUIX_CURRENT_LOCALSTATEDIR
dnl
dnl Determine the localstatedir of an existing Guix installation and set
dnl 'guix_cv_current_localstatedir' accordingly.  Set it to "none" if no
dnl existing installation was found.
AC_DEFUN([GUIX_CURRENT_LOCALSTATEDIR], [
  AC_PATH_PROG([GUILE], [guile])
  AC_CACHE_CHECK([the current installation's localstatedir],
    [guix_cv_current_localstatedir],
    [dnl Call 'dirname' because (guix config) appends "/guix" to LOCALSTATEDIR.
     guix_cv_current_localstatedir="`"$GUILE" \
       -c '(use-modules (guix config))
           (when (string=? %store-directory "'$storedir'")
             (display (dirname %state-directory)))' \
       2>/dev/null`"
     if test "x$guix_cv_current_localstatedir" = "x"; then
       guix_cv_current_localstatedir=none
     fi])])

dnl GUIX_CHECK_LOCALSTATEDIR
dnl
dnl Check that the LOCALSTATEDIR value is consistent with that of the existing
dnl Guix installation, if any.  Error out or warn if they do not match.
AC_DEFUN([GUIX_CHECK_LOCALSTATEDIR], [
  AC_REQUIRE([GUIX_CURRENT_LOCALSTATEDIR])
  if test "x$guix_cv_current_localstatedir" != "xnone"; then
    if test "$guix_cv_current_localstatedir" != "$guix_localstatedir"; then
      case "$localstatedir" in
        NONE|\${prefix}*)
          # User kept the default value---i.e., did not pass '--localstatedir'.
          AC_MSG_ERROR([chosen localstatedir '$guix_localstatedir' does not match \
that of the existing installation '$guix_cv_current_localstatedir'
Installing may corrupt $storedir!
Use './configure --localstatedir=$guix_cv_current_localstatedir'.])
          ;;
        *)
          # User passed an explicit '--localstatedir'.  Assume they know what
          # they're doing.
          AC_MSG_WARN([chosen localstatedir '$guix_localstatedir' does not match \
that of the existing installation '$guix_cv_current_localstatedir'])
          AC_MSG_WARN([installing may corrupt $storedir!])
         ;;
      esac
    fi
  fi])

dnl GUIX_CHANNEL_METADATA
dnl
dnl Provide the channel metadata for this build.  This allows 'guix describe'
dnl to return meaningful data, as it would for a 'guix pull'-provided 'guix'.
dnl The default URL and introduction are taken from (guix channels).
AC_DEFUN([GUIX_CHANNEL_METADATA], [
  AC_ARG_WITH([channel-url], [AS_HELP_STRING([--with-channel-url=URL],
    [assert that this is built from the Git repository at URL])],
    [guix_channel_url="\"$withval\""],
    [guix_channel_url="\"https://git.savannah.gnu.org/git/guix.git\""])
  AC_ARG_WITH([channel-commit], [AS_HELP_STRING([--with-channel-commit=COMMIT],
    [assert that this is built from COMMIT])],
    [guix_channel_commit="\"$withval\""],
    [guix_channel_commit="#f"])
  AC_ARG_WITH([channel-introduction], [AS_HELP_STRING([--with-channel-introduction=COMMIT:FINGERPRINT],
    [specify COMMIT and FINGERPRINT as the introduction of this channel])],
    [guix_channel_introduction="'(\"`echo $withval | cut -f1 -d:`\" \"`echo $withval | cut -f2 -d:`\")"],
    [guix_channel_introduction="'(\"9edb3f66fd807b096b48283debdcddccfea34bad\" . \"BBB0 2DDF 2CEA F6A8 0D1D  E643 A2A0 6DF2 A33A 54FA\")"])

  GUIX_CHANNEL_URL="$guix_channel_url"
  GUIX_CHANNEL_COMMIT="$guix_channel_commit"
  GUIX_CHANNEL_INTRODUCTION="$guix_channel_introduction"

  AC_SUBST([GUIX_CHANNEL_URL])
  AC_SUBST([GUIX_CHANNEL_COMMIT])
  AC_SUBST([GUIX_CHANNEL_INTRODUCTION])
])