diff -ur a/include/gemmi/json.hpp b/include/gemmi/json.hpp
--- a/include/gemmi/json.hpp
+++ b/include/gemmi/json.hpp
@@ -38,6 +38,7 @@
 
 inline std::string as_cif_value(const sajson::value& val) {
   switch (val.get_type()) {
+    case sajson::TYPE_INTEGER:
     case sajson::TYPE_DOUBLE:
       return val.as_string();
     case sajson::TYPE_NULL:
eader'>
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<div class='path'>path: <a href='/guix/log/?id=046fcbae672dccbba76668523c803c63f6727363'>root</a>/<a href='/guix/log/etc?id=046fcbae672dccbba76668523c803c63f6727363'>etc</a>/<a href='/guix/log/etc/committer.scm.in?id=046fcbae672dccbba76668523c803c63f6727363'>committer.scm.in</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/etc/committer.scm.in?id=046fcbae672dccbba76668523c803c63f6727363&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-09-21 15:15:52 +0200'>2021-09-21</span></td><td><a href='/guix/commit/etc/committer.scm.in?id=3d15a19874f63dfc15eb6625558f279ccbc71d5d'>etc: committer: Amend previous commit if a copyright line was added.</a><span class='msg-avail'>...<span class='msg-tooltip'>Previously, the script would raise an error if a copyright line was added to a
file in gnu/packages/.  With this change, it will amend the previous commit
whenever a copyright line is added, and add the copyright line to the commit.

* etc/committer.scm.in (add-copyright-line): New procedure.
(main): Check if a copyright line was added and call ‘add-copyright-line’ if
necessary.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Xinglu Chen</td></tr>
<tr><td><span title='2021-08-10 17:32:19 +0200'>2021-08-10</span></td><td><a href='/guix/commit/etc/committer.scm.in?id=80fc776a614befdae7b2d22f8b154a74e5e679c4'>etc/committer: Pass command-line arguments to main.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/committer.scm.in: Call main with command line arguments.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Sarah Morgensen</td></tr>
<tr><td><span title='2021-08-10 17:32:19 +0200'>2021-08-10</span></td><td><a href='/guix/commit/etc/committer.scm.in?id=73177859bc271e65c7d3c0a44dd7d5103ed8a6db'>etc/committer: Support custom commit messages.</a><span class='msg-avail'>...<span class='msg-tooltip'>Allow custom change commit messages by supplying a commit message and
optionally a changelog message as arguments.

* etc/committer.scm.in (break-string-with-newlines)
(custom-commit-message): New procedures.
(main)[change-commit-message*]: New sub-procedure. Use them.
(main): Use it.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Sarah Morgensen</td></tr>
<tr><td><span title='2021-08-07 14:01:20 +0200'>2021-08-07</span></td><td><a href='/guix/commit/etc/committer.scm.in?id=50c2dcd1c977f98681a4e457b2bcf09d96588eee'>etc: committer: Support reading G-expressions.</a><span class='msg-avail'>...<span class='msg-tooltip'>Some package definitions use G-expressions (see, e.g., chez-scheme).
Import (guix gexp) such that Guile knows how to read those.
Otherwise, an exception such as the following might be raised:

ERROR: In procedure read:
In procedure scm_lreadr: gnu/services/networking.scm:480:16: Unknown # object: #\~

* etc/committer.scm.in: Import (guix gexp).

Signed-off-by: Ricardo Wurmus &lt;rekado@elephly.net&gt;
</span></span></td><td>Maxime Devos</td></tr>