Document the different license base cases

Changed files
+33 -6
doc
+33 -6
doc/meta.xml
···
<varlistentry>
<term><varname>license</varname></term>
-
<listitem><para>The license for the package. One from the
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attribute set defined in <link
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xlink:href="https://github.com/NixOS/nixpkgs/blob/master/lib/licenses.nix">
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<filename>nixpkgs/lib/licenses.nix</filename></link>. Example:
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<literal>stdenv.lib.licenses.gpl3</literal>. For details, see
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<xref linkend='sec-meta-license'/>.</para></listitem>
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<listitem>
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<para>
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The license, or licenses, for the package. One from the attribute set
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defined in <link
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xlink:href="https://github.com/NixOS/nixpkgs/blob/master/lib/licenses.nix">
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<filename>nixpkgs/lib/licenses.nix</filename></link>. At this moment
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using both a list of licenses and a single license is valid. If the
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license field is in the form of a list representation, then it means
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that parts of the package are licensed differently. Each license
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should preferably be referenced by their attribute. The non-list
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attribute value can also be a space delimited string representation of
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the contained attribute shortNames or spdxIds. The following are all valid
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examples:
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<itemizedlist>
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<listitem><para>Single license referenced by attribute (preferred)
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<literal>stdenv.lib.licenses.gpl3</literal>.
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</para></listitem>
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<listitem><para>Single license referenced by its attribute shortName (frowned upon)
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<literal>"gpl3"</literal>.
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</para></listitem>
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<listitem><para>Single license referenced by its attribute spdxId (frowned upon)
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<literal>"GPL-3.0"</literal>.
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</para></listitem>
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<listitem><para>Multiple licenses referenced by attribute (preferred)
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<literal>with stdenv.lib.licenses; [ asl20 free ofl ]</literal>.
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</para></listitem>
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<listitem><para>Multiple licenses referenced as a space delimited string of attribute shortNames (frowned upon)
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<literal>"asl20 free ofl"</literal>.
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</para></listitem>
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</itemizedlist>
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For details, see <xref linkend='sec-meta-license'/>.
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</para>
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</listitem>
</varlistentry>
<varlistentry>