diff options
45 files changed, 1105 insertions, 4349 deletions
diff --git a/doc/coding-conventions.xml b/doc/coding-conventions.xml index 48356247a49e..799f1479467a 100644 --- a/doc/coding-conventions.xml +++ b/doc/coding-conventions.xml @@ -8,24 +8,17 @@ <itemizedlist> <listitem> <para> - Use 2 spaces of indentation per indentation level in Nix expressions, 4 - spaces in shell scripts. + Use 2 spaces of indentation per indentation level in Nix expressions, 4 spaces in shell scripts. </para> </listitem> <listitem> <para> - Do not use tab characters, i.e. configure your editor to use soft tabs. - For instance, use <literal>(setq-default indent-tabs-mode nil)</literal> - in Emacs. Everybody has different tab settings so it’s asking for - trouble. + Do not use tab characters, i.e. configure your editor to use soft tabs. For instance, use <literal>(setq-default indent-tabs-mode nil)</literal> in Emacs. Everybody has different tab settings so it’s asking for trouble. </para> </listitem> <listitem> <para> - Use <literal>lowerCamelCase</literal> for variable names, not - <literal>UpperCamelCase</literal>. Note, this rule does not apply to - package attribute names, which instead follow the rules in - <xref linkend="sec-package-naming"/>. + Use <literal>lowerCamelCase</literal> for variable names, not <literal>UpperCamelCase</literal>. Note, this rule does not apply to package attribute names, which instead follow the rules in <xref linkend="sec-package-naming"/>. </para> </listitem> <listitem> @@ -52,8 +45,7 @@ foo { arg = ...; } </listitem> <listitem> <para> - In attribute sets or lists that span multiple lines, the attribute names - or list elements should be aligned: + In attribute sets or lists that span multiple lines, the attribute names or list elements should be aligned: <programlisting> # A long list. list = [ @@ -97,8 +89,7 @@ attrs = { x = 1280; y = 1024; }; </listitem> <listitem> <para> - Breaking in the middle of a function argument can give hard-to-read code, - like + Breaking in the middle of a function argument can give hard-to-read code, like <programlisting> someFunction { x = 1280; y = 1024; } otherArg @@ -123,8 +114,7 @@ in someFunction res otherArg yetAnotherArg </listitem> <listitem> <para> - The bodies of functions, asserts, and withs are not indented to prevent a - lot of superfluous indentation levels, i.e. + The bodies of functions, asserts, and withs are not indented to prevent a lot of superfluous indentation levels, i.e. <programlisting> { arg1, arg2 }: assert system == "i686-linux"; @@ -156,8 +146,7 @@ stdenv.mkDerivation { ... </listitem> <listitem> <para> - Functions should list their expected arguments as precisely as possible. - That is, write + Functions should list their expected arguments as precisely as possible. That is, write <programlisting> { stdenv, fetchurl, perl }: <replaceable>...</replaceable> </programlisting> @@ -171,9 +160,7 @@ args: with args; <replaceable>...</replaceable> </programlisting> </para> <para> - For functions that are truly generic in the number of arguments (such as - wrappers around <varname>mkDerivation</varname>) that have some required - arguments, you should write them using an <literal>@</literal>-pattern: + For functions that are truly generic in the number of arguments (such as wrappers around <varname>mkDerivation</varname>) that have some required arguments, you should write them using an <literal>@</literal>-pattern: <programlisting> { stdenv, doCoverageAnalysis ? false, ... } @ args: @@ -197,35 +184,20 @@ args.stdenv.mkDerivation (args // { <title>Package naming</title> <para> - The key words <emphasis>must</emphasis>, <emphasis>must not</emphasis>, - <emphasis>required</emphasis>, <emphasis>shall</emphasis>, <emphasis>shall - not</emphasis>, <emphasis>should</emphasis>, <emphasis>should - not</emphasis>, <emphasis>recommended</emphasis>, <emphasis>may</emphasis>, - and <emphasis>optional</emphasis> in this section are to be interpreted as - described in <link xlink:href="https://tools.ietf.org/html/rfc2119">RFC - 2119</link>. Only <emphasis>emphasized</emphasis> words are to be - interpreted in this way. + The key words <emphasis>must</emphasis>, <emphasis>must not</emphasis>, <emphasis>required</emphasis>, <emphasis>shall</emphasis>, <emphasis>shall not</emphasis>, <emphasis>should</emphasis>, <emphasis>should not</emphasis>, <emphasis>recommended</emphasis>, <emphasis>may</emphasis>, and <emphasis>optional</emphasis> in this section are to be interpreted as described in <link xlink:href="https://tools.ietf.org/html/rfc2119">RFC 2119</link>. Only <emphasis>emphasized</emphasis> words are to be interpreted in this way. </para> <para> - In Nixpkgs, there are generally three different names associated with a - package: + In Nixpkgs, there are generally three different names associated with a package: <itemizedlist> <listitem> <para> - The <varname>name</varname> attribute of the derivation (excluding the - version part). This is what most users see, in particular when using - <command>nix-env</command>. + The <varname>name</varname> attribute of the derivation (excluding the version part). This is what most users see, in particular when using <command>nix-env</command>. </para> </listitem> <listitem> <para> - The variable name used for the instantiated package in - <filename>all-packages.nix</filename>, and when passing it as a - dependency to other functions. Typically this is called the - <emphasis>package attribute name</emphasis>. This is what Nix expression - authors see. It can also be used when installing using <command>nix-env - -iA</command>. + The variable name used for the instantiated package in <filename>all-packages.nix</filename>, and when passing it as a dependency to other functions. Typically this is called the <emphasis>package attribute name</emphasis>. This is what Nix expression authors see. It can also be used when installing using <command>nix-env -iA</command>. </para> </listitem> <listitem> @@ -234,12 +206,7 @@ args.stdenv.mkDerivation (args // { </para> </listitem> </itemizedlist> - Most of the time, these are the same. For instance, the package - <literal>e2fsprogs</literal> has a <varname>name</varname> attribute - <literal>"e2fsprogs-<replaceable>version</replaceable>"</literal>, is bound - to the variable name <varname>e2fsprogs</varname> in - <filename>all-packages.nix</filename>, and the Nix expression is in - <filename>pkgs/os-specific/linux/e2fsprogs/default.nix</filename>. + Most of the time, these are the same. For instance, the package <literal>e2fsprogs</literal> has a <varname>name</varname> attribute <literal>"e2fsprogs-<replaceable>version</replaceable>"</literal>, is bound to the variable name <varname>e2fsprogs</varname> in <filename>all-packages.nix</filename>, and the Nix expression is in <filename>pkgs/os-specific/linux/e2fsprogs/default.nix</filename>. </para> <para> @@ -247,51 +214,32 @@ args.stdenv.mkDerivation (args // { <itemizedlist> <listitem> <para> - The <literal>name</literal> attribute <emphasis>should</emphasis> be - identical to the upstream package name. + The <literal>name</literal> attribute <emphasis>should</emphasis> be identical to the upstream package name. </para> </listitem> <listitem> <para> - The <literal>name</literal> attribute <emphasis>must not</emphasis> - contain uppercase letters — e.g., <literal>"mplayer-1.0rc2"</literal> - instead of <literal>"MPlayer-1.0rc2"</literal>. + The <literal>name</literal> attribute <emphasis>must not</emphasis> contain uppercase letters — e.g., <literal>"mplayer-1.0rc2"</literal> instead of <literal>"MPlayer-1.0rc2"</literal>. </para> </listitem> <listitem> <para> - The version part of the <literal>name</literal> attribute - <emphasis>must</emphasis> start with a digit (following a dash) — e.g., - <literal>"hello-0.3.1rc2"</literal>. + The version part of the <literal>name</literal> attribute <emphasis>must</emphasis> start with a digit (following a dash) — e.g., <literal>"hello-0.3.1rc2"</literal>. </para> </listitem> <listitem> <para> - If a package is not a release but a commit from a repository, then the - version part of the name <emphasis>must</emphasis> be the date of that - (fetched) commit. The date <emphasis>must</emphasis> be in - <literal>"YYYY-MM-DD"</literal> format. Also append - <literal>"unstable"</literal> to the name - e.g., - <literal>"pkgname-unstable-2014-09-23"</literal>. + If a package is not a release but a commit from a repository, then the version part of the name <emphasis>must</emphasis> be the date of that (fetched) commit. The date <emphasis>must</emphasis> be in <literal>"YYYY-MM-DD"</literal> format. Also append <literal>"unstable"</literal> to the name - e.g., <literal>"pkgname-unstable-2014-09-23"</literal>. </para> </listitem> <listitem> <para> - Dashes in the package name <emphasis>should</emphasis> be preserved in - new variable names, rather than converted to underscores or camel cased - — e.g., <varname>http-parser</varname> instead of - <varname>http_parser</varname> or <varname>httpParser</varname>. The - hyphenated style is preferred in all three package names. + Dashes in the package name <emphasis>should</emphasis> be preserved in new variable names, rather than converted to underscores or camel cased — e.g., <varname>http-parser</varname> instead of <varname>http_parser</varname> or <varname>httpParser</varname>. The hyphenated style is preferred in all three package names. </para> </listitem> <listitem> <para> - If there are multiple versions of a package, this - <emphasis>should</emphasis> be reflected in the variable names in - <filename>all-packages.nix</filename>, e.g. <varname>json-c-0-9</varname> - and <varname>json-c-0-11</varname>. If there is an obvious “default” - version, make an attribute like <literal>json-c = json-c-0-9;</literal>. - See also <xref linkend="sec-versioning" /> + If there are multiple versions of a package, this <emphasis>should</emphasis> be reflected in the variable names in <filename>all-packages.nix</filename>, e.g. <varname>json-c-0-9</varname> and <varname>json-c-0-11</varname>. If there is an obvious “default” version, make an attribute like <literal>json-c = json-c-0-9;</literal>. See also <xref linkend="sec-versioning" /> </para> </listitem> </itemizedlist> @@ -301,31 +249,18 @@ args.stdenv.mkDerivation (args // { <title>File naming and organisation</title> <para> - Names of files and directories should be in lowercase, with dashes between - words — not in camel case. For instance, it should be - <filename>all-packages.nix</filename>, not - <filename>allPackages.nix</filename> or - <filename>AllPackages.nix</filename>. + Names of files and directories should be in lowercase, with dashes between words — not in camel case. For instance, it should be <filename>all-packages.nix</filename>, not <filename>allPackages.nix</filename> or <filename>AllPackages.nix</filename>. </para> <section xml:id="sec-hierarchy"> <title>Hierarchy</title> <para> - Each package should be stored in its own directory somewhere in the - <filename>pkgs/</filename> tree, i.e. in - <filename>pkgs/<replaceable>category</replaceable>/<replaceable>subcategory</replaceable>/<replaceable>...</replaceable>/<replaceable>pkgname</replaceable></filename>. - Below are some rules for picking the right category for a package. Many - packages fall under several categories; what matters is the - <emphasis>primary</emphasis> purpose of a package. For example, the - <literal>libxml2</literal> package builds both a library and some tools; - but it’s a library foremost, so it goes under - <filename>pkgs/development/libraries</filename>. + Each package should be stored in its own directory somewhere in the <filename>pkgs/</filename> tree, i.e. in <filename>pkgs/<replaceable>category</replaceable>/<replaceable>subcategory</replaceable>/<replaceable>...</replaceable>/<replaceable>pkgname</replaceable></filename>. Below are some rules for picking the right category for a package. Many packages fall under several categories; what matters is the <emphasis>primary</emphasis> purpose of a package. For example, the <literal>libxml2</literal> package builds both a library and some tools; but it’s a library foremost, so it goes under <filename>pkgs/development/libraries</filename>. </para> <para> - When in doubt, consider refactoring the <filename>pkgs/</filename> tree, - e.g. creating new categories or splitting up an existing category. + When in doubt, consider refactoring the <filename>pkgs/</filename> tree, e.g. creating new categories or splitting up an existing category. </para> <variablelist> @@ -341,8 +276,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>development/libraries</filename> (e.g. - <filename>libxml2</filename>) + <filename>development/libraries</filename> (e.g. <filename>libxml2</filename>) </para> </listitem> </varlistentry> @@ -352,8 +286,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>development/compilers</filename> (e.g. - <filename>gcc</filename>) + <filename>development/compilers</filename> (e.g. <filename>gcc</filename>) </para> </listitem> </varlistentry> @@ -363,8 +296,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>development/interpreters</filename> (e.g. - <filename>guile</filename>) + <filename>development/interpreters</filename> (e.g. <filename>guile</filename>) </para> </listitem> </varlistentry> @@ -380,8 +312,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>development/tools/parsing</filename> (e.g. - <filename>bison</filename>, <filename>flex</filename>) + <filename>development/tools/parsing</filename> (e.g. <filename>bison</filename>, <filename>flex</filename>) </para> </listitem> </varlistentry> @@ -391,8 +322,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>development/tools/build-managers</filename> (e.g. - <filename>gnumake</filename>) + <filename>development/tools/build-managers</filename> (e.g. <filename>gnumake</filename>) </para> </listitem> </varlistentry> @@ -402,8 +332,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>development/tools/misc</filename> (e.g. - <filename>binutils</filename>) + <filename>development/tools/misc</filename> (e.g. <filename>binutils</filename>) </para> </listitem> </varlistentry> @@ -429,8 +358,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - (A tool is a relatively small program, especially one intended to be - used non-interactively.) + (A tool is a relatively small program, especially one intended to be used non-interactively.) </para> <variablelist> <varlistentry> @@ -439,8 +367,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>tools/networking</filename> (e.g. - <filename>wget</filename>) + <filename>tools/networking</filename> (e.g. <filename>wget</filename>) </para> </listitem> </varlistentry> @@ -470,8 +397,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>tools/archivers</filename> (e.g. <filename>zip</filename>, - <filename>tar</filename>) + <filename>tools/archivers</filename> (e.g. <filename>zip</filename>, <filename>tar</filename>) </para> </listitem> </varlistentry> @@ -481,8 +407,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>tools/compression</filename> (e.g. - <filename>gzip</filename>, <filename>bzip2</filename>) + <filename>tools/compression</filename> (e.g. <filename>gzip</filename>, <filename>bzip2</filename>) </para> </listitem> </varlistentry> @@ -492,8 +417,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>tools/security</filename> (e.g. <filename>nmap</filename>, - <filename>gnupg</filename>) + <filename>tools/security</filename> (e.g. <filename>nmap</filename>, <filename>gnupg</filename>) </para> </listitem> </varlistentry> @@ -532,8 +456,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>servers/http</filename> (e.g. - <filename>apache-httpd</filename>) + <filename>servers/http</filename> (e.g. <filename>apache-httpd</filename>) </para> </listitem> </varlistentry> @@ -543,8 +466,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>servers/x11</filename> (e.g. <filename>xorg</filename> — - this includes the client libraries and programs) + <filename>servers/x11</filename> (e.g. <filename>xorg</filename> — this includes the client libraries and programs) </para> </listitem> </varlistentry> @@ -567,8 +489,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>desktops</filename> (e.g. <filename>kde</filename>, - <filename>gnome</filename>, <filename>enlightenment</filename>) + <filename>desktops</filename> (e.g. <filename>kde</filename>, <filename>gnome</filename>, <filename>enlightenment</filename>) </para> </listitem> </varlistentry> @@ -578,8 +499,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>applications/window-managers</filename> (e.g. - <filename>awesome</filename>, <filename>stumpwm</filename>) + <filename>applications/window-managers</filename> (e.g. <filename>awesome</filename>, <filename>stumpwm</filename>) </para> </listitem> </varlistentry> @@ -589,8 +509,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - A (typically large) program with a distinct user interface, primarily - used interactively. + A (typically large) program with a distinct user interface, primarily used interactively. </para> <variablelist> <varlistentry> @@ -599,8 +518,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>applications/version-management</filename> (e.g. - <filename>subversion</filename>) + <filename>applications/version-management</filename> (e.g. <filename>subversion</filename>) </para> </listitem> </varlistentry> @@ -610,8 +528,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>applications/video</filename> (e.g. - <filename>vlc</filename>) + <filename>applications/video</filename> (e.g. <filename>vlc</filename>) </para> </listitem> </varlistentry> @@ -621,8 +538,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>applications/graphics</filename> (e.g. - <filename>gimp</filename>) + <filename>applications/graphics</filename> (e.g. <filename>gimp</filename>) </para> </listitem> </varlistentry> @@ -638,8 +554,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>applications/networking/mailreaders</filename> (e.g. - <filename>thunderbird</filename>) + <filename>applications/networking/mailreaders</filename> (e.g. <filename>thunderbird</filename>) </para> </listitem> </varlistentry> @@ -649,8 +564,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>applications/networking/newsreaders</filename> (e.g. - <filename>pan</filename>) + <filename>applications/networking/newsreaders</filename> (e.g. <filename>pan</filename>) </para> </listitem> </varlistentry> @@ -660,8 +574,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>applications/networking/browsers</filename> (e.g. - <filename>firefox</filename>) + <filename>applications/networking/browsers</filename> (e.g. <filename>firefox</filename>) </para> </listitem> </varlistentry> @@ -719,8 +632,7 @@ args.stdenv.mkDerivation (args // { </term> <listitem> <para> - <filename>data/sgml+xml/schemas/xml-dtd</filename> (e.g. - <filename>docbook</filename>) + <filename>data/sgml+xml/schemas/xml-dtd</filename> (e.g. <filename>docbook</filename>) </para> </listitem> </varlistentry> @@ -733,8 +645,7 @@ args.stdenv.mkDerivation (args // { (Okay, these are executable...) </para> <para> - <filename>data/sgml+xml/stylesheets/xslt</filename> (e.g. - <filename>docbook-xsl</filename>) + <filename>data/sgml+xml/stylesheets/xslt</filename> (e.g. <filename>docbook-xsl</filename>) </para> </listitem> </varlistentry> @@ -771,36 +682,15 @@ args.stdenv.mkDerivation (args // { <title>Versioning</title> <para> - Because every version of a package in Nixpkgs creates a potential - maintenance burden, old versions of a package should not be kept unless - there is a good reason to do so. For instance, Nixpkgs contains several - versions of GCC because other packages don’t build with the latest - version of GCC. Other examples are having both the latest stable and latest - pre-release version of a package, or to keep several major releases of an - application that differ significantly in functionality. + Because every version of a package in Nixpkgs creates a potential maintenance burden, old versions of a package should not be kept unless there is a good reason to do so. For instance, Nixpkgs contains several versions of GCC because other packages don’t build with the latest version of GCC. Other examples are having both the latest stable and latest |