perl-net-dns-resolver-programmable used the undocumented and internal
method Net::DNS::rcodesbyname [0], and that interface is no longer
exposed.

This patch, copied from [1], makes the program check for the existence
of the method before trying to use it.

[0]
<https://rt.cpan.org/Public/Bug/Display.html?id=95901>

[1]
<https://rt.cpan.org/Public/Bug/Display.html?id=95901#txn-1575108>

diff --git a/lib/Net/DNS/Resolver/Programmable.pm b/lib/Net/DNS/Resolver/Programmable.pm
index 1af72ce..e09a2f0 100644
--- a/lib/Net/DNS/Resolver/Programmable.pm
+++ b/lib/Net/DNS/Resolver/Programmable.pm
@@ -203,8 +203,10 @@ sub send {
     if (defined(my $resolver_code = $self->{resolver_code})) {
         ($result, $aa, @answer_rrs) = $resolver_code->($domain, $rr_type, $class);
     }
-    
-    if (not defined($result) or defined($Net::DNS::rcodesbyname{$result})) {
+
+    if (not defined($result)
+         or defined($Net::DNS::Parameters::rcodebyname{$result})
+         or defined($Net::DNS::rcodesbyname{$result})) {
         # Valid RCODE, return a packet:
         
         $aa     = TRUE      if not defined($aa);
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<div class='path'>path: <a href='/guix/log/?id=57be690d912ad9e1683f80d4de2e1076ae27948d'>root</a>/<a href='/guix/log/gnu?id=57be690d912ad9e1683f80d4de2e1076ae27948d'>gnu</a>/<a href='/guix/log/gnu/packages?id=57be690d912ad9e1683f80d4de2e1076ae27948d'>packages</a>/<a href='/guix/log/gnu/packages/agda.scm?id=57be690d912ad9e1683f80d4de2e1076ae27948d'>agda.scm</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/gnu/packages/agda.scm?id=57be690d912ad9e1683f80d4de2e1076ae27948d&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2018-10-01 12:12:23 +0200'>2018-10-01</span></td><td><a href='/guix/commit/gnu/packages/agda.scm?id=787231e9570779892b2eb2e79563be4cfacc9b9d'>gnu: agda: Fix build.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-10-01 12:12:18 +0200'>2018-10-01</span></td><td><a href='/guix/commit/gnu/packages/agda.scm?id=5ebadb584bc642d58bf6c8dbb54468e4b7f266bd'>gnu: agda: Update to 2.5.4.1.</a><span class='msg-avail'>...</span></td><td>Timothy Sample</td></tr>
<tr><td><span title='2018-10-01 12:12:08 +0200'>2018-10-01</span></td><td><a href='/guix/commit/gnu/packages/agda.scm?id=f54f04756f6d90c9fb3b5e45f3947329287f9b05'>gnu: ghc-mtl: Remove built-in Haskell package.</a><span class='msg-avail'>...</span></td><td>Timothy Sample</td></tr>
<tr><td><span title='2018-07-29 23:33:40 +0200'>2018-07-29</span></td><td><a href='/guix/commit/gnu/packages/agda.scm?id=1237653aa5c555bc6b621b6402b26064db2e668e'>gnu: Add emacs-agda2-mode</a><span class='msg-avail'>...</span></td><td>Alex ter Weele</td></tr>
<tr><td><span title='2018-07-29 23:32:01 +0200'>2018-07-29</span></td><td><a href='/guix/commit/gnu/packages/agda.scm?id=253340dcc8c44acb4c687ebcc56e6f17167c5659'>gnu: agda: Compile .agda files.</a><span class='msg-avail'>...</span></td><td>Alex ter Weele</td></tr>
<tr><td><span title='2018-02-26 01:42:35 +0100'>2018-02-26</span></td><td><a href='/guix/commit/gnu/packages/agda.scm?id=f61682e7ea87db3eed7e67adacd1d3f8c1b7c119'>gnu: Add agda.</a><span class='msg-avail'>...</span></td><td>Alex ter Weele</td></tr>