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<!DOCTYPE html>

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  <section id="expert-python-r1-usage">
<h1>Expert python-r1 usage<a class="headerlink" href="#expert-python-r1-usage" title="Link to this heading"></a></h1>
<p>The APIs described in this chapter are powerful but even harder to use
than those described in <code class="docutils literal notranslate"><span class="pre">python-r1</span></code> chapter.  You should not consider
using them unless you have a proper ninja training.</p>
<section id="partially-restricting-python-implementation">
<span id="index-0"></span><h2>Partially restricting Python implementation<a class="headerlink" href="#partially-restricting-python-implementation" title="Link to this heading"></a></h2>
<p>There are packages that have been ported to Python 3 only partially.
They may still have some optional dependencies that support Python 2
only, they may have some components that do not support Python 3 yet.
The opposite is also possible — some of the features being available
only for Python 3.</p>
<p>There are two approaches to this problem.  You can either skip features
(ignore USE flags) if the necessary implementation is not enabled,
or you can use <code class="docutils literal notranslate"><span class="pre">REQUIRED_USE</span></code> to enforce at least one interpreter
having the requested feature.</p>
<p>Skipping specific tasks can be done via investigating <code class="docutils literal notranslate"><span class="pre">${EPYTHON}</span></code>.
If USE flags are involved, you will probably also need to use
<code class="docutils literal notranslate"><span class="pre">python_gen_cond_dep</span></code> with additional parameters restricting
dependencies to available targets.</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="c1"># Copyright 1999-2020 Gentoo Authors</span>
<span class="w"> </span><span class="c1"># Distributed under the terms of the GNU General Public License v2</span>

<span class="w"> </span><span class="nv">EAPI</span><span class="o">=</span><span class="m">7</span>

<span class="w"> </span><span class="nv">PYTHON_COMPAT</span><span class="o">=(</span><span class="w"> </span>python2_7<span class="w"> </span>python3_<span class="o">{</span><span class="m">6</span>,7,8<span class="o">}</span><span class="w"> </span>pypy<span class="o">{</span>,3<span class="o">}</span><span class="w"> </span><span class="o">)</span>
<span class="w"> </span><span class="nv">PYTHON_REQ_USE</span><span class="o">=</span><span class="s2">&quot;threads(+)&quot;</span>
<span class="w"> </span>inherit<span class="w"> </span>distutils-r1

<span class="w"> </span><span class="nv">DESCRIPTION</span><span class="o">=</span><span class="s2">&quot;HTTP library for human beings&quot;</span>
<span class="w"> </span><span class="nv">HOMEPAGE</span><span class="o">=</span><span class="s2">&quot;http://python-requests.org/&quot;</span>
<span class="w"> </span><span class="nv">SRC_URI</span><span class="o">=</span><span class="s2">&quot;mirror://pypi/</span><span class="si">${</span><span class="nv">P</span><span class="p">:</span><span class="nv">0</span><span class="p">:</span><span class="nv">1</span><span class="si">}</span><span class="s2">/</span><span class="si">${</span><span class="nv">PN</span><span class="si">}</span><span class="s2">/</span><span class="si">${</span><span class="nv">P</span><span class="si">}</span><span class="s2">.tar.gz&quot;</span>

<span class="w"> </span><span class="nv">LICENSE</span><span class="o">=</span><span class="s2">&quot;Apache-2.0&quot;</span>
<span class="w"> </span><span class="nv">SLOT</span><span class="o">=</span><span class="s2">&quot;0&quot;</span>
<span class="w"> </span><span class="nv">KEYWORDS</span><span class="o">=</span><span class="s2">&quot;~amd64 ~arm ~arm64 ~sparc ~x86 ~amd64-linux ~x86-linux&quot;</span>
<span class="w"> </span><span class="nv">IUSE</span><span class="o">=</span><span class="s2">&quot;socks5 +ssl test&quot;</span>
<span class="w"> </span><span class="nv">RESTRICT</span><span class="o">=</span><span class="s2">&quot;!test? ( test )&quot;</span>

<span class="w"> </span><span class="nv">RDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     &gt;=dev-python/certifi-2017.4.17[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &gt;=dev-python/chardet-3.0.2[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &lt;dev-python/chardet-4[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &gt;=dev-python/idna-2.5[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &lt;dev-python/idna-3[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &lt;dev-python/urllib3-1.26[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     socks5? ( &gt;=dev-python/PySocks-1.5.6[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">] )</span>
<span class="s2">     ssl? (</span>
<span class="s2">         &gt;=dev-python/cryptography-1.3.4[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">         &gt;=dev-python/pyopenssl-0.14[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     )</span>
<span class="s2"> &quot;</span>

<span class="w"> </span><span class="nv">BDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     dev-python/setuptools[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     test? (</span>
<span class="hll"><span class="s2">         </span><span class="k">$(</span>python_gen_cond_dep<span class="w"> </span><span class="s1">&#39;</span>
</span><span class="hll"><span class="s1">             ${RDEPEND}</span>
</span><span class="hll"><span class="s1">             dev-python/pytest[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">             dev-python/pytest-httpbin[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">             dev-python/pytest-mock[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">             &gt;=dev-python/PySocks-1.5.6[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">         &#39;</span><span class="w"> </span><span class="s1">&#39;python*&#39;</span><span class="k">)</span>
</span><span class="s2">     )</span>
<span class="s2"> &quot;</span>

<span class="w"> </span>python_test<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="w">     </span><span class="c1"># tests hang with pypy &amp; pypy3</span>
<span class="hll"><span class="w">     </span><span class="o">[[</span><span class="w"> </span><span class="si">${</span><span class="nv">EPYTHON</span><span class="si">}</span><span class="w"> </span><span class="o">==</span><span class="w"> </span>pypy*<span class="w"> </span><span class="o">]]</span><span class="w"> </span><span class="o">&amp;&amp;</span><span class="w"> </span><span class="k">continue</span>
</span>
<span class="w">     </span>epytest
<span class="w"> </span><span class="o">}</span>
</pre></div>
</div>
<p>Enforcing implementations is done via putting <code class="docutils literal notranslate"><span class="pre">||</span></code> block with all
targets providing the feature in <code class="docutils literal notranslate"><span class="pre">REQUIRED_USE</span></code>.  The eclass provides
<code class="docutils literal notranslate"><span class="pre">python_gen_useflags</span></code> function to print valid flag names for specified
implementation list.  Please always use this function instead of listing
actual flag names as it handled phasing implementations out gracefully.
<code class="docutils literal notranslate"><span class="pre">python_gen_cond_dep</span></code> should also be called with matching target
list.</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="c1"># Copyright 1999-2020 Gentoo Authors</span>
<span class="w"> </span><span class="c1"># Distributed under the terms of the GNU General Public License v2</span>

<span class="w"> </span><span class="nv">EAPI</span><span class="o">=</span><span class="m">7</span>

<span class="w"> </span><span class="nv">PYTHON_COMPAT</span><span class="o">=(</span><span class="w"> </span>python3_<span class="o">{</span><span class="m">6</span>,7,8<span class="o">}</span><span class="w"> </span><span class="o">)</span>
<span class="w"> </span><span class="nv">PYTHON_REQ_USE</span><span class="o">=</span><span class="s2">&quot;sqlite&quot;</span>
<span class="w"> </span>inherit<span class="w"> </span>distutils-r1

<span class="w"> </span><span class="nv">DESCRIPTION</span><span class="o">=</span><span class="s2">&quot;Toolkit to convert between many translation formats&quot;</span>
<span class="w"> </span><span class="nv">HOMEPAGE</span><span class="o">=</span><span class="s2">&quot;https://github.com/translate/translate&quot;</span>
<span class="w"> </span><span class="nv">SRC_URI</span><span class="o">=</span><span class="s2">&quot;https://github.com/translate/translate/releases/download/</span><span class="si">${</span><span class="nv">PV</span><span class="si">}</span><span class="s2">/</span><span class="si">${</span><span class="nv">P</span><span class="si">}</span><span class="s2">.tar.gz&quot;</span>

<span class="w"> </span><span class="nv">LICENSE</span><span class="o">=</span><span class="s2">&quot;GPL-2&quot;</span>
<span class="w"> </span><span class="nv">SLOT</span><span class="o">=</span><span class="s2">&quot;0&quot;</span>
<span class="w"> </span><span class="nv">KEYWORDS</span><span class="o">=</span><span class="s2">&quot;amd64 arm64 x86 ~amd64-linux ~x86-linux&quot;</span>
<span class="w"> </span><span class="nv">IUSE</span><span class="o">=</span><span class="s2">&quot;+subtitles&quot;</span>
<span class="w"> </span><span class="nv">REQUIRED_USE</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">PYTHON_REQUIRED_USE</span><span class="si">}</span>
<span class="hll"><span class="s2">     subtitles? ( || ( </span><span class="k">$(</span>python_gen_useflags<span class="w"> </span>python3_<span class="o">{</span><span class="m">6</span>,7<span class="o">}</span><span class="k">)</span><span class="s2"> ) )&quot;</span>
</span>
<span class="w"> </span><span class="nv">DEPEND</span><span class="o">=</span><span class="s2">&quot;&gt;=dev-python/six-1.10.0[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span>
<span class="w"> </span><span class="nv">RDEPEND</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">DEPEND</span><span class="si">}</span>
<span class="s2">     !dev-python/pydiff</span>
<span class="s2">     app-text/iso-codes</span>
<span class="s2">     &gt;=dev-python/chardet-3.0.4[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &gt;=dev-python/lxml-3.5[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &gt;=dev-python/pycountry-18.5.26[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     &gt;=dev-python/python-levenshtein-0.12.0[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">     sys-devel/gettext</span>
<span class="s2">     subtitles? (</span>
<span class="hll"><span class="s2">         </span><span class="k">$(</span>python_gen_cond_dep<span class="w"> </span><span class="s1">&#39;</span>
</span><span class="hll"><span class="s1">             media-video/gaupol[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">         &#39;</span><span class="w"> </span>python3_<span class="o">{</span><span class="m">6</span>,7<span class="o">}</span><span class="k">)</span>
</span><span class="s2">     )</span>
<span class="s2"> &quot;</span>
</pre></div>
</div>
</section>
<section id="restricting-interpreters-for-python-setup">
<span id="index-2"></span><span id="index-1"></span><h2>Restricting interpreters for python_setup<a class="headerlink" href="#restricting-interpreters-for-python-setup" title="Link to this heading"></a></h2>
<p>A specific case of the restriction described above is when the build
step supports a subset of Python targets for the runtime part.  This
could happen e.g. if package’s Python bindings have been ported
to Python 3 but the test suite or building tooling still requires
Python 2.</p>
<p>To support this use case, <code class="docutils literal notranslate"><span class="pre">python_setup</span></code> can optionally take a list
of implementations.  This list must be a subset of <code class="docutils literal notranslate"><span class="pre">PYTHON_COMPAT</span></code>,
and only implementation on the list can be used by <code class="docutils literal notranslate"><span class="pre">python_setup</span></code>.
Note that you also need to set matching <code class="docutils literal notranslate"><span class="pre">REQUIRED_USE</span></code>, as otherwise
the function will fail if the user does not enable any of the supported
targets.</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="c1"># Copyright 1999-2020 Gentoo Authors</span>
<span class="w"> </span><span class="c1"># Distributed under the terms of the GNU General Public License v2</span>

<span class="w"> </span><span class="nv">EAPI</span><span class="o">=</span><span class="m">6</span>

<span class="w"> </span><span class="nv">PYTHON_COMPAT</span><span class="o">=(</span><span class="w"> </span>python2_7<span class="w"> </span>python3_<span class="o">{</span><span class="m">5</span>,6,7<span class="o">}</span><span class="w"> </span><span class="o">)</span>

<span class="w"> </span>inherit<span class="w"> </span>python-r1<span class="w"> </span>toolchain-funcs

<span class="w"> </span><span class="nv">DESCRIPTION</span><span class="o">=</span><span class="s2">&quot;Python extension module generator for C and C++ libraries&quot;</span>
<span class="w"> </span><span class="nv">HOMEPAGE</span><span class="o">=</span><span class="s2">&quot;https://www.riverbankcomputing.com/software/sip/intro&quot;</span>
<span class="w"> </span><span class="nv">SRC_URI</span><span class="o">=</span><span class="s2">&quot;https://www.riverbankcomputing.com/static/Downloads/</span><span class="si">${</span><span class="nv">PN</span><span class="si">}</span><span class="s2">/</span><span class="si">${</span><span class="nv">PV</span><span class="si">}</span><span class="s2">/</span><span class="si">${</span><span class="nv">P</span><span class="si">}</span><span class="s2">.tar.gz&quot;</span>

<span class="w"> </span><span class="c1"># Sub-slot based on SIP_API_MAJOR_NR from siplib/sip.h</span>
<span class="w"> </span><span class="nv">SLOT</span><span class="o">=</span><span class="s2">&quot;0/12&quot;</span>
<span class="w"> </span><span class="nv">LICENSE</span><span class="o">=</span><span class="s2">&quot;|| ( GPL-2 GPL-3 SIP )&quot;</span>
<span class="w"> </span><span class="nv">KEYWORDS</span><span class="o">=</span><span class="s2">&quot;alpha amd64 arm arm64 ~hppa ia64 ppc ppc64 ~sparc x86 ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~x86-macos&quot;</span>
<span class="w"> </span><span class="nv">REQUIRED_USE</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">PYTHON_REQUIRED_USE</span><span class="si">}</span>
<span class="hll"><span class="s2">     || ( </span><span class="k">$(</span>python_gen_useflags<span class="w"> </span><span class="s1">&#39;python2*&#39;</span><span class="k">)</span><span class="s2"> )&quot;</span>
</span>
<span class="w"> </span><span class="nv">RDEPEND</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">PYTHON_DEPS</span><span class="si">}</span><span class="s2">&quot;</span>
<span class="w"> </span><span class="nv">DEPEND</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">RDEPEND</span><span class="si">}</span>
<span class="s2">     sys-devel/bison</span>
<span class="s2">     sys-devel/flex</span>

<span class="s2"> src_prepare() {</span>
<span class="hll"><span class="s2">     python_setup &#39;python2*&#39;</span>
</span><span class="s2">     &quot;</span><span class="si">${</span><span class="nv">EPYTHON</span><span class="si">}</span><span class="s2">&quot; build.py prepare || die</span>
<span class="s2">     default</span>
<span class="s2"> }</span>

<span class="s2"> src_configure() {</span>
<span class="s2">     configuration() {</span>
<span class="s2">         local myconf=(</span>
<span class="s2">             &quot;</span><span class="si">${</span><span class="nv">EPYTHON</span><span class="si">}</span><span class="s2">&quot;</span>
<span class="s2">             &quot;</span><span class="si">${</span><span class="nv">S</span><span class="si">}</span><span class="s2">&quot;/configure.py</span>
<span class="s2">             --bindir=&quot;</span><span class="si">${</span><span class="nv">EPREFIX</span><span class="si">}</span>/usr/bin<span class="s2">&quot;</span>
<span class="s2">             --destdir=&quot;</span><span class="k">$(</span>python_get_sitedir<span class="k">)</span><span class="s2">&quot;</span>
<span class="s2">             --incdir=&quot;</span><span class="k">$(</span>python_get_includedir<span class="k">)</span><span class="s2">&quot;</span>
<span class="s2">         )</span>
<span class="s2">         echo &quot;</span><span class="si">${</span><span class="nv">myconf</span><span class="p">[@]</span><span class="si">}</span><span class="s2">&quot;</span>
<span class="s2">         &quot;</span><span class="si">${</span><span class="nv">myconf</span><span class="p">[@]</span><span class="si">}</span><span class="s2">&quot; || die</span>
<span class="s2">     }</span>
<span class="s2">     python_foreach_impl run_in_build_dir configuration</span>
<span class="s2"> }</span>

<span class="s2"> src_compile() {</span>
<span class="s2">     python_foreach_impl run_in_build_dir default</span>
<span class="s2"> }</span>

<span class="s2"> src_install() {</span>
<span class="s2">     installation() {</span>
<span class="s2">         emake DESTDIR=&quot;</span><span class="si">${</span><span class="nv">D</span><span class="si">}</span><span class="s2">&quot; install</span>
<span class="s2">         python_optimize</span>
<span class="s2">     }</span>
<span class="s2">     python_foreach_impl run_in_build_dir installation</span>

<span class="s2">     einstalldocs</span>
<span class="s2"> }</span>
</pre></div>
</div>
<p>The <code class="docutils literal notranslate"><span class="pre">distutils-r1</span></code> equivalent of <code class="docutils literal notranslate"><span class="pre">python_setup</span></code> parameters is
the <code class="docutils literal notranslate"><span class="pre">DISTUTILS_ALL_SUBPHASE_IMPLS</span></code> variable.  Alternatively to global
scope, it can be set in an early phase function (prior to any sub-phase
call).</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="c1"># Copyright 1999-2020 Gentoo Authors</span>
<span class="w"> </span><span class="c1"># Distributed under the terms of the GNU General Public License v2</span>

<span class="w"> </span><span class="nv">EAPI</span><span class="o">=</span><span class="m">5</span>

<span class="w"> </span><span class="nv">PYTHON_COMPAT</span><span class="o">=(</span>
<span class="w">     </span>pypy
<span class="w">     </span>python3_5<span class="w"> </span>python3_6<span class="w"> </span>python3_7
<span class="w">     </span>python2_7
<span class="w"> </span><span class="o">)</span>
<span class="w"> </span><span class="nv">PYTHON_REQ_USE</span><span class="o">=</span><span class="s1">&#39;bzip2(+),ssl(+),threads(+)&#39;</span>
<span class="w"> </span>inherit<span class="w"> </span>distutils-r1

<span class="w"> </span><span class="nv">DESCRIPTION</span><span class="o">=</span><span class="s2">&quot;Portage is the package management and distribution system for Gentoo&quot;</span>
<span class="w"> </span><span class="nv">HOMEPAGE</span><span class="o">=</span><span class="s2">&quot;https://wiki.gentoo.org/wiki/Project:Portage&quot;</span>
<span class="w"> </span><span class="nv">SRC_URI</span><span class="o">=</span><span class="s2">&quot;mirror://gentoo/</span><span class="si">${</span><span class="nv">P</span><span class="si">}</span><span class="s2">.tar.bz2&quot;</span>

<span class="w"> </span><span class="nv">LICENSE</span><span class="o">=</span><span class="s2">&quot;GPL-2&quot;</span>
<span class="w"> </span><span class="nv">KEYWORDS</span><span class="o">=</span><span class="s2">&quot;~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~m68k ~mips ~ppc ~ppc64 ~riscv ~s390 ~sh ~sparc ~x86&quot;</span>
<span class="w"> </span><span class="nv">SLOT</span><span class="o">=</span><span class="s2">&quot;0&quot;</span>
<span class="w"> </span><span class="nv">IUSE</span><span class="o">=</span><span class="s2">&quot;epydoc&quot;</span>
<span class="hll"><span class="w"> </span><span class="nv">REQUIRED_USE</span><span class="o">=</span><span class="s2">&quot;epydoc? ( </span><span class="k">$(</span>python_gen_useflags<span class="w"> </span><span class="s1">&#39;python2*&#39;</span><span class="k">)</span><span class="s2"> )&quot;</span>
</span>
<span class="w"> </span><span class="nv">DEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     &gt;=app-arch/tar-1.27</span>
<span class="s2">     &gt;=sys-apps/sed-4.0.5 sys-devel/patch</span>
<span class="s2">     epydoc? (</span>
<span class="hll"><span class="s2">         </span><span class="k">$(</span>python_gen_cond_dep<span class="w"> </span><span class="s1">&#39;</span>
</span><span class="hll"><span class="s1">             &gt;=dev-python/epydoc-2.0[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">         &#39;</span><span class="w"> </span><span class="s1">&#39;python2*&#39;</span><span class="k">)</span>
</span><span class="s2">     )&quot;</span>
<span class="w"> </span><span class="nv">RDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     &gt;=app-arch/tar-1.27</span>
<span class="s2">     dev-lang/python-exec:2</span>
<span class="s2">     &gt;=sys-apps/sed-4.0.5</span>
<span class="s2">     app-shells/bash:0[readline]</span>
<span class="s2">     &gt;=app-admin/eselect-1.2</span>
<span class="s2">     elibc_glibc? ( &gt;=sys-apps/sandbox-2.2 )</span>
<span class="s2">     kernel_linux? ( sys-apps/util-linux )</span>
<span class="s2">     &gt;=app-misc/pax-utils-0.1.17&quot;</span>
<span class="w"> </span><span class="nv">PDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     &gt;=net-misc/rsync-2.6.4</span>
<span class="s2">     userland_GNU? ( &gt;=sys-apps/coreutils-6.4 )&quot;</span>

<span class="w"> </span>pkg_setup<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="hll"><span class="w">     </span>use<span class="w"> </span>epydoc<span class="w"> </span><span class="o">&amp;&amp;</span><span class="w"> </span><span class="nv">DISTUTILS_ALL_SUBPHASE_IMPLS</span><span class="o">=(</span><span class="w"> </span>python2.7<span class="w"> </span><span class="o">)</span>
</span><span class="w"> </span><span class="o">}</span>

<span class="w"> </span>python_compile_all<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="w">     </span><span class="k">if</span><span class="w"> </span>use<span class="w"> </span>epydoc<span class="p">;</span><span class="w"> </span><span class="k">then</span>
<span class="w">         </span>esetup.py<span class="w"> </span>epydoc
<span class="w">     </span><span class="k">fi</span>
<span class="w"> </span><span class="o">}</span>
</pre></div>
</div>
<p>Note that when the restriction is caused by dependencies rather than
package’s files, the any-r1 API described below is preferable to this.</p>
</section>
<section id="disjoint-build-dependencies-any-r1-api">
<span id="index-4"></span><span id="index-3"></span><h2>Disjoint build dependencies (any-r1 API)<a class="headerlink" href="#disjoint-build-dependencies-any-r1-api" title="Link to this heading"></a></h2>
<p>Some packages have disjoint sets of runtime and pure build-time
dependencies.  The former need to be built for all enabled
implementations, the latter only for one of them.  The any-r1 API
in <code class="docutils literal notranslate"><span class="pre">python-r1</span></code> is specifically suited for expressing that.</p>
<p>Let’s consider an example package that uses Sphinx with a plugin
to build documentation.  Naturally, you’re going to build the documents
only once, not separately for every enabled target.</p>
<section id="using-regular-python-r1-api">
<h3>Using regular python-r1 API<a class="headerlink" href="#using-regular-python-r1-api" title="Link to this heading"></a></h3>
<p>If you were using the regular API, you’d have to use
<code class="docutils literal notranslate"><span class="pre">${PYTHON_USEDEP}</span></code> on the dependencies.  The resulting code could look
like the following:</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="nv">BDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">    doc? (</span>
<span class="s2">        dev-python/sphinx[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">        dev-python/sphinx_rtd_theme[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]</span>
<span class="s2">    )&quot;</span>

src_compile<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="w">    </span>...

<span class="w">    </span><span class="k">if</span><span class="w"> </span>use<span class="w"> </span>doc<span class="p">;</span><span class="w"> </span><span class="k">then</span>
<span class="w">        </span>python_setup
<span class="w">        </span>emake<span class="w"> </span>-C<span class="w"> </span>docs<span class="w"> </span>html
<span class="w">    </span><span class="k">fi</span>
<span class="o">}</span>
</pre></div>
</div>
<p>If your package is built with support for Python 3.6, 3.7 and 3.8,
then this dependency string will enforce the same targets for Sphinx
and the theme.  However, in practice it will only be used through
Python 3.8.  Normally, this is not such a big deal.</p>
<p>Now imagine your package supports Python 2.7 as well, while Sphinx
does not anymore.  This means that your package will force downgrade
to the old version of <code class="docutils literal notranslate"><span class="pre">dev-python/sphinx</span></code> even though it will not
be used via Python 2.7 at all.</p>
</section>
<section id="using-any-r1-api-with-python-r1">
<h3>Using any-r1 API with python-r1<a class="headerlink" href="#using-any-r1-api-with-python-r1" title="Link to this heading"></a></h3>
<p>As the name suggests, the any-r1 API resembles the API used
by <code class="docutils literal notranslate"><span class="pre">python-any-r1</span></code> eclass.  The disjoint build-time dependencies
are declared using <code class="docutils literal notranslate"><span class="pre">python_gen_any_dep</span></code>, and need to be tested
via <code class="docutils literal notranslate"><span class="pre">python_check_deps()</span></code> function.  The presence of the latter
function activates the alternate behavior of <code class="docutils literal notranslate"><span class="pre">python_setup</span></code>.  Instead
of selecting one of the enabled targets, it will run it to verify
installed dependencies and use one having all dependencies satisfied.</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="nv">BDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     doc? (</span>
<span class="hll"><span class="s2">         </span><span class="k">$(</span>python_gen_any_dep<span class="w"> </span><span class="s1">&#39;</span>
</span><span class="hll"><span class="s1">             dev-python/sphinx[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">             dev-python/sphinx_rtd_theme[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">         &#39;</span><span class="k">)</span>
</span><span class="s2">     )&quot;</span>

<span class="hll"><span class="w"> </span>python_check_deps<span class="o">()</span><span class="w"> </span><span class="o">{</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;dev-python/sphinx[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span><span class="w"> </span><span class="o">&amp;&amp;</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;dev-python/sphinx_rtd_theme[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span>
</span><span class="hll"><span class="w"> </span><span class="o">}</span>
</span>
<span class="w"> </span>src_compile<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="w">     </span>...

<span class="w">     </span><span class="k">if</span><span class="w"> </span>use<span class="w"> </span>doc<span class="p">;</span><span class="w"> </span><span class="k">then</span>
<span class="hll"><span class="w">         </span>python_setup
</span><span class="w">         </span>emake<span class="w"> </span>-C<span class="w"> </span>docs<span class="w"> </span>html
<span class="w">     </span><span class="k">fi</span>
<span class="w"> </span><span class="o">}</span>
</pre></div>
</div>
<p>Note that <code class="docutils literal notranslate"><span class="pre">python_setup</span></code> may select an implementation that is not even
enabled via <code class="docutils literal notranslate"><span class="pre">PYTHON_TARGETS</span></code>.  The goal is to try hard to avoid
requiring user to change USE flags on dependencies if possible.</p>
<p>An interesting side effect of that is that the supported targets
in the dependencies can be a subset of the one in package.  For example,
we have used this API to add Python 3.8 support to packages before
<code class="docutils literal notranslate"><span class="pre">dev-python/sphinx</span></code> supported it — the eclass implicitly forced using
another implementation for Sphinx.</p>
</section>
<section id="different-sets-of-build-time-dependencies">
<h3>Different sets of build-time dependencies<a class="headerlink" href="#different-sets-of-build-time-dependencies" title="Link to this heading"></a></h3>
<p>Let’s consider the case when Python is used at build-time for something
else still.  In that case, we want <code class="docutils literal notranslate"><span class="pre">python_setup</span></code> to work
unconditionally but enforce dependencies only with <code class="docutils literal notranslate"><span class="pre">doc</span></code> flag enabled.</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="nv">BDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     doc? (</span>
<span class="s2">         </span><span class="k">$(</span>python_gen_any_dep<span class="w"> </span><span class="s1">&#39;</span>
<span class="s1">             dev-python/sphinx[${PYTHON_USEDEP}]</span>
<span class="s1">             dev-python/sphinx_rtd_theme[${PYTHON_USEDEP}]</span>
<span class="s1">         &#39;</span><span class="k">)</span>
<span class="s2">     )&quot;</span>

<span class="hll"><span class="w"> </span>python_check_deps<span class="o">()</span><span class="w"> </span><span class="o">{</span>
</span><span class="hll"><span class="w">     </span>use<span class="w"> </span>doc<span class="w"> </span><span class="o">||</span><span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="m">0</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;dev-python/sphinx[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span><span class="w"> </span><span class="o">&amp;&amp;</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;dev-python/sphinx_rtd_theme[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span>
</span><span class="hll"><span class="w"> </span><span class="o">}</span>
</span>
<span class="w"> </span>src_compile<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="hll"><span class="w">     </span>python_setup
</span>
<span class="w">     </span>...

<span class="w">     </span>use<span class="w"> </span>doc<span class="w"> </span><span class="o">&amp;&amp;</span><span class="w"> </span>emake<span class="w"> </span>-C<span class="w"> </span>docs<span class="w"> </span>html
<span class="w"> </span><span class="o">}</span>
</pre></div>
</div>
<p>Note that <code class="docutils literal notranslate"><span class="pre">python_setup</span></code> behaves according to the any-r1 API here.
While it will not enforce doc dependencies with <code class="docutils literal notranslate"><span class="pre">doc</span></code> flag disabled,
it will use <em>any</em> interpreter that is supported and installed, even
if it is not enabled explicitly in <code class="docutils literal notranslate"><span class="pre">PYTHON_TARGETS</span></code>.</p>
</section>
<section id="using-any-r1-api-with-distutils-r1">
<h3>Using any-r1 API with distutils-r1<a class="headerlink" href="#using-any-r1-api-with-distutils-r1" title="Link to this heading"></a></h3>
<p>The alternate build dependency API also integrates with <code class="docutils literal notranslate"><span class="pre">distutils-r1</span></code>
eclass.  If <code class="docutils literal notranslate"><span class="pre">python_check_deps()</span></code> is declared, the <code class="docutils literal notranslate"><span class="pre">python_*_all()</span></code>
sub-phase functions are called with the interpreter selected according
to any-r1 rules.</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="nv">BDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     doc? (</span>
<span class="hll"><span class="s2">         </span><span class="k">$(</span>python_gen_any_dep<span class="w"> </span><span class="s1">&#39;</span>
</span><span class="hll"><span class="s1">             dev-python/sphinx[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">             dev-python/sphinx_rtd_theme[${PYTHON_USEDEP}]</span>
</span><span class="hll"><span class="s1">         &#39;</span><span class="k">)</span>
</span><span class="s2">     )&quot;</span>

<span class="hll"><span class="w"> </span>python_check_deps<span class="o">()</span><span class="w"> </span><span class="o">{</span>
</span><span class="hll"><span class="w">     </span>use<span class="w"> </span>doc<span class="w"> </span><span class="o">||</span><span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="m">0</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;dev-python/sphinx[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span><span class="w"> </span><span class="o">&amp;&amp;</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;dev-python/sphinx_rtd_theme[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span>
</span><span class="hll"><span class="w"> </span><span class="o">}</span>
</span>
<span class="w"> </span>python_compile_all<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="w">     </span>use<span class="w"> </span>doc<span class="w"> </span><span class="o">&amp;&amp;</span><span class="w"> </span>emake<span class="w"> </span>-C<span class="w"> </span>docs<span class="w"> </span>html
<span class="w"> </span><span class="o">}</span>
</pre></div>
</div>
<p>Note that <code class="docutils literal notranslate"><span class="pre">distutils-r1</span></code> calls <code class="docutils literal notranslate"><span class="pre">python_setup</span></code> unconditionally,
therefore <code class="docutils literal notranslate"><span class="pre">python_check_deps()</span></code> needs to account for that.</p>
<p>Normally you won’t have to use this API for Sphinx though —
<code class="docutils literal notranslate"><span class="pre">distutils_enable_sphinx</span></code> does precisely that for you.</p>
</section>
</section>
<section id="combining-any-r1-api-with-implementation-restrictions">
<h2>Combining any-r1 API with implementation restrictions<a class="headerlink" href="#combining-any-r1-api-with-implementation-restrictions" title="Link to this heading"></a></h2>
<p>Both APIs described above can be combined.  This can be used when
build-time scripts support a subset of implementations supported
by the package itself, and by its build-time dependencies.  For example,
if the package uses <code class="docutils literal notranslate"><span class="pre">dev-util/scons</span></code> build system with <code class="docutils literal notranslate"><span class="pre">SConstruct</span></code>
files using Python 2 construct.</p>
<p>There are two approaches to achieve that: either the build-time
implementation list needs to be passed to <code class="docutils literal notranslate"><span class="pre">python_setup</span></code>,
or <code class="docutils literal notranslate"><span class="pre">python_check_deps</span></code> needs to explicitly reject unsupported targets.
In both cases, a matching implementation list needs to be passed
to <code class="docutils literal notranslate"><span class="pre">python_gen_any_dep</span></code>.</p>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="c1"># Copyright 1999-2020 Gentoo Authors</span>
<span class="w"> </span><span class="c1"># Distributed under the terms of the GNU General Public License v2</span>

<span class="w"> </span><span class="nv">EAPI</span><span class="o">=</span><span class="m">7</span>

<span class="w"> </span><span class="nv">PYTHON_COMPAT</span><span class="o">=(</span><span class="w"> </span>python2_7<span class="w"> </span>python3_6<span class="w"> </span><span class="o">)</span>
<span class="w"> </span>inherit<span class="w"> </span>python-r1<span class="w"> </span>toolchain-funcs

<span class="w"> </span><span class="nv">DESCRIPTION</span><span class="o">=</span><span class="s2">&quot;GPS daemon and library for USB/serial GPS devices and GPS/mapping clients&quot;</span>
<span class="w"> </span><span class="nv">HOMEPAGE</span><span class="o">=</span><span class="s2">&quot;https://gpsd.gitlab.io/gpsd/&quot;</span>
<span class="w"> </span><span class="nv">SRC_URI</span><span class="o">=</span><span class="s2">&quot;mirror://nongnu/</span><span class="si">${</span><span class="nv">PN</span><span class="si">}</span><span class="s2">/</span><span class="si">${</span><span class="nv">P</span><span class="si">}</span><span class="s2">.tar.gz&quot;</span>

<span class="w"> </span><span class="nv">LICENSE</span><span class="o">=</span><span class="s2">&quot;BSD&quot;</span>
<span class="w"> </span><span class="nv">SLOT</span><span class="o">=</span><span class="s2">&quot;0/24&quot;</span>
<span class="w"> </span><span class="nv">KEYWORDS</span><span class="o">=</span><span class="s2">&quot;~amd64 ~arm ~ppc ~ppc64 ~sparc ~x86&quot;</span>

<span class="w"> </span><span class="nv">IUSE</span><span class="o">=</span><span class="s2">&quot;python&quot;</span>
<span class="w"> </span><span class="nv">REQUIRED_USE</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     python? ( </span><span class="si">${</span><span class="nv">PYTHON_REQUIRED_USE</span><span class="si">}</span><span class="s2"> )&quot;</span>

<span class="w"> </span><span class="nv">RDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     &gt;=net-misc/pps-tools-0.0.20120407</span>
<span class="s2">     python? ( </span><span class="si">${</span><span class="nv">PYTHON_DEPS</span><span class="si">}</span><span class="s2"> )&quot;</span>
<span class="w"> </span><span class="nv">DEPEND</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">RDEPEND</span><span class="si">}</span>
<span class="hll"><span class="s2">     </span><span class="k">$(</span>python_gen_any_dep<span class="w"> </span><span class="s1">&#39;&gt;=dev-util/scons-2.3.0[${PYTHON_USEDEP}]&#39;</span><span class="w"> </span>-2<span class="k">)</span>
</span><span class="s2">     virtual/pkgconfig&quot;</span>

<span class="hll"><span class="w"> </span>python_check_deps<span class="o">()</span><span class="w"> </span><span class="o">{</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;&gt;=dev-util/scons-2.3.0[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span>
</span><span class="hll"><span class="w"> </span><span class="o">}</span>
</span>
<span class="w"> </span>src_configure<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="w">     </span><span class="nv">myesconsargs</span><span class="o">=(</span>
<span class="w">         </span><span class="nv">prefix</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">EPREFIX</span><span class="si">}</span><span class="s2">/usr&quot;</span>
<span class="w">         </span><span class="nv">libdir</span><span class="o">=</span><span class="s2">&quot;\$prefix/</span><span class="k">$(</span>get_libdir<span class="k">)</span><span class="s2">&quot;</span>
<span class="w">         </span><span class="nv">udevdir</span><span class="o">=</span><span class="s2">&quot;</span><span class="k">$(</span>get_udevdir<span class="k">)</span><span class="s2">&quot;</span>
<span class="w">         </span><span class="nv">chrpath</span><span class="o">=</span>False
<span class="w">         </span><span class="nv">gpsd_user</span><span class="o">=</span>gpsd
<span class="w">         </span><span class="nv">gpsd_group</span><span class="o">=</span>uucp
<span class="w">         </span><span class="nv">nostrip</span><span class="o">=</span>True
<span class="w">         </span><span class="nv">manbuild</span><span class="o">=</span>False
<span class="w">         </span><span class="k">$(</span>use_scons<span class="w"> </span>python<span class="k">)</span>
<span class="w">     </span><span class="o">)</span>

<span class="w">     </span><span class="c1"># SConstruct uses py2 constructs</span>
<span class="hll"><span class="w">     </span>python_setup<span class="w"> </span>-2
</span><span class="w"> </span><span class="o">}</span>
</pre></div>
</div>
<div class="highlight-bash notranslate"><div class="highlight"><pre><span></span><span class="w"> </span><span class="c1"># Copyright 1999-2020 Gentoo Authors</span>
<span class="w"> </span><span class="c1"># Distributed under the terms of the GNU General Public License v2</span>

<span class="w"> </span><span class="nv">EAPI</span><span class="o">=</span><span class="m">7</span>

<span class="w"> </span><span class="nv">PYTHON_COMPAT</span><span class="o">=(</span><span class="w"> </span>python2_7<span class="w"> </span>python3_6<span class="w"> </span><span class="o">)</span>
<span class="w"> </span>inherit<span class="w"> </span>python-r1<span class="w"> </span>toolchain-funcs

<span class="w"> </span><span class="nv">DESCRIPTION</span><span class="o">=</span><span class="s2">&quot;GPS daemon and library for USB/serial GPS devices and GPS/mapping clients&quot;</span>
<span class="w"> </span><span class="nv">HOMEPAGE</span><span class="o">=</span><span class="s2">&quot;https://gpsd.gitlab.io/gpsd/&quot;</span>
<span class="w"> </span><span class="nv">SRC_URI</span><span class="o">=</span><span class="s2">&quot;mirror://nongnu/</span><span class="si">${</span><span class="nv">PN</span><span class="si">}</span><span class="s2">/</span><span class="si">${</span><span class="nv">P</span><span class="si">}</span><span class="s2">.tar.gz&quot;</span>

<span class="w"> </span><span class="nv">LICENSE</span><span class="o">=</span><span class="s2">&quot;BSD&quot;</span>
<span class="w"> </span><span class="nv">SLOT</span><span class="o">=</span><span class="s2">&quot;0/24&quot;</span>
<span class="w"> </span><span class="nv">KEYWORDS</span><span class="o">=</span><span class="s2">&quot;~amd64 ~arm ~ppc ~ppc64 ~sparc ~x86&quot;</span>

<span class="w"> </span><span class="nv">IUSE</span><span class="o">=</span><span class="s2">&quot;python&quot;</span>
<span class="w"> </span><span class="nv">REQUIRED_USE</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     python? ( </span><span class="si">${</span><span class="nv">PYTHON_REQUIRED_USE</span><span class="si">}</span><span class="s2"> )&quot;</span>

<span class="w"> </span><span class="nv">RDEPEND</span><span class="o">=</span><span class="s2">&quot;</span>
<span class="s2">     &gt;=net-misc/pps-tools-0.0.20120407</span>
<span class="s2">     python? ( </span><span class="si">${</span><span class="nv">PYTHON_DEPS</span><span class="si">}</span><span class="s2"> )&quot;</span>
<span class="w"> </span><span class="nv">DEPEND</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">RDEPEND</span><span class="si">}</span>
<span class="hll"><span class="s2">     </span><span class="k">$(</span>python_gen_any_dep<span class="w"> </span><span class="s1">&#39;&gt;=dev-util/scons-2.3.0[${PYTHON_USEDEP}]&#39;</span><span class="w"> </span>-2<span class="k">)</span>
</span><span class="s2">     virtual/pkgconfig&quot;</span>

<span class="hll"><span class="w"> </span>python_check_deps<span class="o">()</span><span class="w"> </span><span class="o">{</span>
</span><span class="hll"><span class="w">     </span>python_is_python3<span class="w"> </span><span class="o">&amp;&amp;</span><span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="m">1</span>
</span><span class="hll"><span class="w">     </span>python_has_version<span class="w"> </span><span class="s2">&quot;&gt;=dev-util/scons-2.3.0[</span><span class="si">${</span><span class="nv">PYTHON_USEDEP</span><span class="si">}</span><span class="s2">]&quot;</span>
</span><span class="hll"><span class="w"> </span><span class="o">}</span>
</span>
<span class="w"> </span>src_configure<span class="o">()</span><span class="w"> </span><span class="o">{</span>
<span class="w">     </span><span class="nv">myesconsargs</span><span class="o">=(</span>
<span class="w">         </span><span class="nv">prefix</span><span class="o">=</span><span class="s2">&quot;</span><span class="si">${</span><span class="nv">EPREFIX</span><span class="si">}</span><span class="s2">/usr&quot;</span>
<span class="w">         </span><span class="nv">libdir</span><span class="o">=</span><span class="s2">&quot;\$prefix/</span><span class="k">$(</span>get_libdir<span class="k">)</span><span class="s2">&quot;</span>
<span class="w">         </span><span class="nv">udevdir</span><span class="o">=</span><span class="s2">&quot;</span><span class="k">$(</span>get_udevdir<span class="k">)</span><span class="s2">&quot;</span>
<span class="w">         </span><span class="nv">chrpath</span><span class="o">=</span>False
<span class="w">         </span><span class="nv">gpsd_user</span><span class="o">=</span>gpsd
<span class="w">         </span><span class="nv">gpsd_group</span><span class="o">=</span>uucp
<span class="w">         </span><span class="nv">nostrip</span><span class="o">=</span>True
<span class="w">         </span><span class="nv">manbuild</span><span class="o">=</span>False
<span class="w">         </span><span class="k">$(</span>use_scons<span class="w"> </span>python<span class="k">)</span>
<span class="w">     </span><span class="o">)</span>

<span class="hll"><span class="w">     </span>python_setup
</span><span class="w"> </span><span class="o">}</span>
</pre></div>
</div>
</section>
</section>


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