11 files changed, 173 insertions, 186 deletions
diff --git a/doc/functions/debug.section.md b/doc/functions/debug.section.md
new file mode 100644
index 00000000000..b2d8589431a
--- /dev/null
+++ b/doc/functions/debug.section.md
@@ -0,0 +1,5 @@
+# Debugging Nix Expressions {#sec-debug}
+
+Nix is a unityped, dynamic language, this means every value can potentially appear anywhere. Since it is also non-strict, evaluation order and what ultimately is evaluated might surprise you. Therefore it is important to be able to debug nix expressions.
+
+In the `lib/debug.nix` file you will find a number of functions that help (pretty-)printing values while evaluation is running. You can even specify how deep these values should be printed recursively, and transform them on the fly. Please consult the docstrings in `lib/debug.nix` for usage information.
diff --git a/doc/functions/debug.xml b/doc/functions/debug.xml
deleted file mode 100644
index c27421f12e7..00000000000
--- a/doc/functions/debug.xml
+++ /dev/null
@@ -1,14 +0,0 @@
-<section xmlns="http://docbook.org/ns/docbook"
-         xmlns:xlink="http://www.w3.org/1999/xlink"
-         xmlns:xi="http://www.w3.org/2001/XInclude"
-         xml:id="sec-debug">
- <title>Debugging Nix Expressions</title>
-
- <para>
-  Nix is a unityped, dynamic language, this means every value can potentially appear anywhere. Since it is also non-strict, evaluation order and what ultimately is evaluated might surprise you. Therefore it is important to be able to debug nix expressions.
- </para>
-
- <para>
-  In the <literal>lib/debug.nix</literal> file you will find a number of functions that help (pretty-)printing values while evaluation is runnnig. You can even specify how deep these values should be printed recursively, and transform them on the fly. Please consult the docstrings in <literal>lib/debug.nix</literal> for usage information.
- </para>
-</section>
diff --git a/doc/functions/generators.section.md b/doc/functions/generators.section.md
new file mode 100644
index 00000000000..d54e5027c79
--- /dev/null
+++ b/doc/functions/generators.section.md
@@ -0,0 +1,56 @@
+# Generators {#sec-generators}
+Generators are functions that create file formats from nix data structures, e. g. for configuration files. There are generators available for: `INI`, `JSON` and `YAML`
+
+All generators follow a similar call interface: `generatorName configFunctions data`, where `configFunctions` is an attrset of user-defined functions that format nested parts of the content. They each have common defaults, so often they do not need to be set manually. An example is `mkSectionName ? (name: libStr.escape [ "[" "]" ] name)` from the `INI` generator. It receives the name of a section and sanitizes it. The default `mkSectionName` escapes `[` and `]` with a backslash.
+
+Generators can be fine-tuned to produce exactly the file format required by your application/service. One example is an INI-file format which uses `: ` as separator, the strings `"yes"`/`"no"` as boolean values and requires all string values to be quoted:
+
+```nix
+with lib;
+let
+  customToINI = generators.toINI {
+    # specifies how to format a key/value pair
+    mkKeyValue = generators.mkKeyValueDefault {
+      # specifies the generated string for a subset of nix values
+      mkValueString = v:
+             if v == true then ''"yes"''
+        else if v == false then ''"no"''
+        else if isString v then ''"${v}"''
+        # and delegats all other values to the default generator
+        else generators.mkValueStringDefault {} v;
+    } ":";
+  };
+
+# the INI file can now be given as plain old nix values
+in customToINI {
+  main = {
+    pushinfo = true;
+    autopush = false;
+    host = "localhost";
+    port = 42;
+  };
+  mergetool = {
+    merge = "diff3";
+  };
+}
+```
+
+This will produce the following INI file as nix string:
+
+```INI
+[main]
+autopush:"no"
+host:"localhost"
+port:42
+pushinfo:"yes"
+str\:ange:"very::strange"
+
+[mergetool]
+merge:"diff3"
+```
+
+::: {.note}
+Nix store paths can be converted to strings by enclosing a derivation attribute like so: `"${drv}"`.
+:::
+
+Detailed documentation for each generator can be found in `lib/generators.nix`.
diff --git a/doc/functions/generators.xml b/doc/functions/generators.xml
deleted file mode 100644
index 9ce1f85eb17..00000000000
--- a/doc/functions/generators.xml
+++ /dev/null
@@ -1,74 +0,0 @@
-<section xmlns="http://docbook.org/ns/docbook"
-         xmlns:xlink="http://www.w3.org/1999/xlink"
-         xmlns:xi="http://www.w3.org/2001/XInclude"
-         xml:id="sec-generators">
- <title>Generators</title>
-
- <para>
-  Generators are functions that create file formats from nix data structures, e. g. for configuration files. There are generators available for: <literal>INI</literal>, <literal>JSON</literal> and <literal>YAML</literal>
- </para>
-
- <para>
-  All generators follow a similar call interface: <code>generatorName configFunctions data</code>, where <literal>configFunctions</literal> is an attrset of user-defined functions that format nested parts of the content. They each have common defaults, so often they do not need to be set manually. An example is <code>mkSectionName ? (name: libStr.escape [ "[" "]" ] name)</code> from the <literal>INI</literal> generator. It receives the name of a section and sanitizes it. The default <literal>mkSectionName</literal> escapes <literal>[</literal> and <literal>]</literal> with a backslash.
- </para>
-
- <para>
-  Generators can be fine-tuned to produce exactly the file format required by your application/service. One example is an INI-file format which uses <literal>: </literal> as separator, the strings <literal>"yes"</literal>/<literal>"no"</literal> as boolean values and requires all string values to be quoted:
- </para>
-
-<programlisting>
-with lib;
-let
-  customToINI = generators.toINI {
-    # specifies how to format a key/value pair
-    mkKeyValue = generators.mkKeyValueDefault {
-      # specifies the generated string for a subset of nix values
-      mkValueString = v:
-             if v == true then ''"yes"''
-        else if v == false then ''"no"''
-        else if isString v then ''"${v}"''
-        # and delegats all other values to the default generator
-        else generators.mkValueStringDefault {} v;
-    } ":";
-  };
-
-# the INI file can now be given as plain old nix values
-in customToINI {
-  main = {
-    pushinfo = true;
-    autopush = false;
-    host = "localhost";
-    port = 42;
-  };
-  mergetool = {
-    merge = "diff3";
-  };
-}
-</programlisting>
-
- <para>
-  This will produce the following INI file as nix string:
- </para>
-
-<programlisting>
-[main]
-autopush:"no"
-host:"localhost"
-port:42
-pushinfo:"yes"
-str\:ange:"very::strange"
-
-[mergetool]
-merge:"diff3"
-</programlisting>
-
- <note>
-  <para>
-   Nix store paths can be converted to strings by enclosing a derivation attribute like so: <code>"${drv}"</code>.
-  </para>
- </note>
-
- <para>
-  Detailed documentation for each generator can be found in <literal>lib/generators.nix</literal>.
- </para>
-</section>
diff --git a/doc/functions/library.xml b/doc/functions/library.xml
index 6ffb944b5a6..21bcf5b88c9 100644
--- a/doc/functions/library.xml
+++ b/doc/functions/library.xml
@@ -25,4 +25,6 @@
  <xi:include href="./library/generated/debug.xml" />
 
  <xi:include href="./library/generated/options.xml" />
+
+ <xi:include href="./library/generated/sources.xml" />
 </section>
diff --git a/doc/functions/library/asserts.xml b/doc/functions/library/asserts.xml
index 10891039e86..7c94222ef13 100644
--- a/doc/functions/library/asserts.xml
+++ b/doc/functions/library/asserts.xml
@@ -103,7 +103,7 @@ stderr> assert failed
    <title>Ensuring a user provided a possible value</title>
 <programlisting><![CDATA[
 let sslLibrary = "bearssl";
-in lib.asserts.assertOneOf "sslLibrary" sslLibrary [ "openssl" "bearssl" ];
+in lib.asserts.assertOneOf "sslLibrary" sslLibrary [ "openssl" "libressl" ];
 => false
 stderr> trace: sslLibrary must be one of "openssl", "libressl", but is: "bearssl"
         ]]></programlisting>
diff --git a/doc/functions/library/attrsets.xml b/doc/functions/library/attrsets.xml
index 3c5823c2589..ef132514da1 100644
--- a/doc/functions/library/attrsets.xml
+++ b/doc/functions/library/attrsets.xml
@@ -7,7 +7,7 @@
  <section xml:id="function-library-lib.attrsets.attrByPath">
   <title><function>lib.attrset.attrByPath</function></title>
 
-  <subtitle><literal>attrByPath :: [String] -> Any -> AttrSet</literal>
+  <subtitle><literal>attrByPath :: [String] -> Any -> AttrSet -> Any</literal>
   </subtitle>
 
   <xi:include href="./locations.xml" xpointer="lib.attrsets.attrByPath" />
@@ -166,7 +166,7 @@ lib.attrsets.setAttrByPath [ "a" "b" ] 3
   <xi:include href="./locations.xml" xpointer="lib.attrsets.getAttrFromPath" />
 
   <para>
-   Like <xref linkend="function-library-lib.attrsets.attrByPath" /> except without a default, and it will throw if the value doesn't exist.
+   Like [](#function-library-lib.attrsets.attrByPath) except without a default, and it will throw if the value doesn't exist.
   </para>
 
   <variablelist>
@@ -855,7 +855,7 @@ lib.attrsets.mapAttrs' (name: value: lib.attrsets.nameValuePair ("foo_" + name)
   <title><function>lib.attrsets.mapAttrsToList</function></title>
 
   <subtitle><literal>mapAttrsToList :: (String -> Any -> Any) ->
-   AttrSet -> Any</literal>
+   AttrSet -> [Any]</literal>
   </subtitle>
 
   <xi:include href="./locations.xml" xpointer="lib.attrsets.mapAttrsToList" />
@@ -1480,7 +1480,7 @@ lib.attrsets.zipAttrsWith
   <xi:include href="./locations.xml" xpointer="lib.attrsets.zipAttrs" />
 
   <para>
-   Merge sets of attributes and combine each attribute value in to a list. Similar to <xref linkend="function-library-lib.attrsets.zipAttrsWith" /> where the merge function returns a list of all values.
+   Merge sets of attributes and combine each attribute value in to a list. Similar to [](#function-library-lib.attrsets.zipAttrsWith) where the merge function returns a list of all values.
   </para>
 
   <variablelist>
@@ -1677,8 +1677,7 @@ recursiveUpdate
   <xi:include href="./locations.xml" xpointer="lib.attrsets.recurseIntoAttrs" />
 
   <para>
-   Make various Nix tools consider the contents of the resulting
-   attribute set when looking for what to build, find, etc.
+   Make various Nix tools consider the contents of the resulting attribute set when looking for what to build, find, etc.
   </para>
 
   <para>
@@ -1711,4 +1710,42 @@ recursiveUpdate
   </example>
  </section>
 
+ <section xml:id="function-library-lib.attrsets.cartesianProductOfSets">
+  <title><function>lib.attrsets.cartesianProductOfSets</function></title>
+
+  <subtitle><literal>cartesianProductOfSets :: AttrSet -> [ AttrSet ]</literal>
+  </subtitle>
+
+  <xi:include href="./locations.xml" xpointer="lib.attrsets.cartesianProductOfSets" />
+
+  <para>
+   Return the cartesian product of attribute set value combinations.
+  </para>
+
+  <variablelist>
+   <varlistentry>
+    <term>
+     <varname>set</varname>
+    </term>
+    <listitem>
+     <para>
+      An attribute set with attributes that carry lists of values.
+     </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+
+  <example xml:id="function-library-lib.attrsets.cartesianProductOfSets-example">
+   <title>Creating the cartesian product of a list of attribute values</title>
+<programlisting><![CDATA[
+cartesianProductOfSets { a = [ 1 2 ]; b = [ 10 20 ]; }
+=> [
+     { a = 1; b = 10; }
+     { a = 1; b = 20; }
+     { a = 2; b = 10; }
+     { a = 2; b = 20; }
+   ]
+]]></programlisting>
+  </example>
+ </section>
 </section>
diff --git a/doc/functions/nix-gitignore.section.md b/doc/functions/nix-gitignore.section.md
new file mode 100644
index 00000000000..2fb833b2300
--- /dev/null
+++ b/doc/functions/nix-gitignore.section.md
@@ -0,0 +1,49 @@
+# pkgs.nix-gitignore {#sec-pkgs-nix-gitignore}
+
+`pkgs.nix-gitignore` is a function that acts similarly to `builtins.filterSource` but also allows filtering with the help of the gitignore format.
+
+## Usage {#sec-pkgs-nix-gitignore-usage}
+
+`pkgs.nix-gitignore` exports a number of functions, but you\'ll most likely need either `gitignoreSource` or `gitignoreSourcePure`. As their first argument, they both accept either 1. a file with gitignore lines or 2. a string with gitignore lines, or 3. a list of either of the two. They will be concatenated into a single big string.
+
+```nix
+{ pkgs ? import <nixpkgs> {} }:
+
+ nix-gitignore.gitignoreSource [] ./source
+     # Simplest version
+
+ nix-gitignore.gitignoreSource "supplemental-ignores\n" ./source
+     # This one reads the ./source/.gitignore and concats the auxiliary ignores
+
+ nix-gitignore.gitignoreSourcePure "ignore-this\nignore-that\n" ./source
+     # Use this string as gitignore, don't read ./source/.gitignore.
+
+ nix-gitignore.gitignoreSourcePure ["ignore-this\nignore-that\n", ~/.gitignore] ./source
+     # It also accepts a list (of strings and paths) that will be concatenated
+     # once the paths are turned to strings via readFile.
+```
+
+These functions are derived from the `Filter` functions by setting the first filter argument to `(_: _: true)`:
+
+```nix
+gitignoreSourcePure = gitignoreFilterSourcePure (_: _: true);
+gitignoreSource = gitignoreFilterSource (_: _: true);
+```
+
+Those filter functions accept the same arguments the `builtins.filterSource` function would pass to its filters, thus `fn: gitignoreFilterSourcePure fn ""` should be extensionally equivalent to `filterSource`. The file is blacklisted if it\'s blacklisted by either your filter or the gitignoreFilter.
+
+If you want to make your own filter from scratch, you may use
+
+```nix
+gitignoreFilter = ign: root: filterPattern (gitignoreToPatterns ign) root;
+```
+
+## gitignore files in subdirectories {#sec-pkgs-nix-gitignore-usage-recursive}
+
+If you wish to use a filter that would search for .gitignore files in subdirectories, just like git does by default, use this function:
+
+```nix
+gitignoreFilterRecursiveSource = filter: patterns: root:
+# OR
+gitignoreRecursiveSource = gitignoreFilterSourcePure (_: _: true);
+```
diff --git a/doc/functions/nix-gitignore.xml b/doc/functions/nix-gitignore.xml
deleted file mode 100644
index 37a82b196cc..00000000000
--- a/doc/functions/nix-gitignore.xml
+++ /dev/null
@@ -1,70 +0,0 @@
-<section xmlns="http://docbook.org/ns/docbook"
-         xmlns:xlink="http://www.w3.org/1999/xlink"
-         xmlns:xi="http://www.w3.org/2001/XInclude"
-         xml:id="sec-pkgs-nix-gitignore">
- <title>pkgs.nix-gitignore</title>
-
- <para>
-  <function>pkgs.nix-gitignore</function> is a function that acts similarly to <literal>builtins.filterSource</literal> but also allows filtering with the help of the gitignore format.
- </para>
-
- <section xml:id="sec-pkgs-nix-gitignore-usage">
-  <title>Usage</title>
-
-  <para>
-   <literal>pkgs.nix-gitignore</literal> exports a number of functions, but you'll most likely need either <literal>gitignoreSource</literal> or <literal>gitignoreSourcePure</literal>. As their first argument, they both accept either 1. a file with gitignore lines or 2. a string with gitignore lines, or 3. a list of either of the two. They will be concatenated into a single big string.
-  </para>
-
-<programlisting><![CDATA[
-{ pkgs ? import <nixpkgs> {} }:
-
- nix-gitignore.gitignoreSource [] ./source
-     # Simplest version
-
- nix-gitignore.gitignoreSource "supplemental-ignores\n" ./source
-     # This one reads the ./source/.gitignore and concats the auxiliary ignores
-
- nix-gitignore.gitignoreSourcePure "ignore-this\nignore-that\n" ./source
-     # Use this string as gitignore, don't read ./source/.gitignore.
-
- nix-gitignore.gitignoreSourcePure ["ignore-this\nignore-that\n", ~/.gitignore] ./source
-     # It also accepts a list (of strings and paths) that will be concatenated
-     # once the paths are turned to strings via readFile.
-  ]]></programlisting>
-
-  <para>
-   These functions are derived from the <literal>Filter</literal> functions by setting the first filter argument to <literal>(_: _: true)</literal>:
-  </para>
-
-<programlisting><![CDATA[
-gitignoreSourcePure = gitignoreFilterSourcePure (_: _: true);
-gitignoreSource = gitignoreFilterSource (_: _: true);
-  ]]></programlisting>
-
-  <para>
-   Those filter functions accept the same arguments the <literal>builtins.filterSource</literal> function would pass to its filters, thus <literal>fn: gitignoreFilterSourcePure fn ""</literal> should be extensionally equivalent to <literal>filterSource</literal>. The file is blacklisted iff it's blacklisted by either your filter or the gitignoreFilter.
-  </para>
-
-  <para>
-   If you want to make your own filter from scratch, you may use
-  </para>
-
-<programlisting><![CDATA[
-gitignoreFilter = ign: root: filterPattern (gitignoreToPatterns ign) root;
-  ]]></programlisting>
- </section>
-
- <section xml:id="sec-pkgs-nix-gitignore-usage-recursive">
-  <title>gitignore files in subdirectories</title>
-
-  <para>
-   If you wish to use a filter that would search for .gitignore files in subdirectories, just like git does by default, use this function:
-  </para>
-
-<programlisting><![CDATA[
-gitignoreFilterRecursiveSource = filter: patterns: root:
-# OR
-gitignoreRecursiveSource = gitignoreFilterSourcePure (_: _: true);
-  ]]></programlisting>
- </section>
-</section>
diff --git a/doc/functions/prefer-remote-fetch.section.md b/doc/functions/prefer-remote-fetch.section.md
new file mode 100644
index 00000000000..8760c100224
--- /dev/null
+++ b/doc/functions/prefer-remote-fetch.section.md
@@ -0,0 +1,17 @@
+# prefer-remote-fetch overlay {#sec-prefer-remote-fetch}
+
+`prefer-remote-fetch` is an overlay that download sources on remote builder. This is useful when the evaluating machine has a slow upload while the builder can fetch faster directly from the source. To use it, put the following snippet as a new overlay:
+
+```nix
+self: super:
+  (super.prefer-remote-fetch self super)
+```
+
+A full configuration example for that sets the overlay up for your own account, could look like this
+
+```ShellSession
+$ mkdir ~/.config/nixpkgs/overlays/
+$ cat > ~/.config/nixpkgs/overlays/prefer-remote-fetch.nix <<EOF
+  self: super: super.prefer-remote-fetch self super
+EOF
+```
diff --git a/doc/functions/prefer-remote-fetch.xml b/doc/functions/prefer-remote-fetch.xml
deleted file mode 100644
index 94d25d3d3ae..00000000000
--- a/doc/functions/prefer-remote-fetch.xml
+++ /dev/null
@@ -1,21 +0,0 @@
-<section xmlns="http://docbook.org/ns/docbook"
-         xmlns:xlink="http://www.w3.org/1999/xlink"
-         xmlns:xi="http://www.w3.org/2001/xinclude"
-         xml:id="sec-prefer-remote-fetch">
- <title>prefer-remote-fetch overlay</title>
-
- <para>
-  <function>prefer-remote-fetch</function> is an overlay that download sources on remote builder. This is useful when the evaluating machine has a slow upload while the builder can fetch faster directly from the source. To use it, put the following snippet as a new overlay:
-<programlisting>
-self: super:
-  (super.prefer-remote-fetch self super)
-</programlisting>
-  A full configuration example for that sets the overlay up for your own account, could look like this
-<screen>
-<prompt>$ </prompt>mkdir ~/.config/nixpkgs/overlays/
-<prompt>$ </prompt>cat &gt; ~/.config/nixpkgs/overlays/prefer-remote-fetch.nix &lt;&lt;EOF
-  self: super: super.prefer-remote-fetch self super
-EOF
-</screen>
- </para>
-</section>