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-rw-r--r--doc/manual/expressions/builtins.xml129
-rw-r--r--doc/manual/expressions/derivations.xml2
-rw-r--r--doc/manual/expressions/language-values.xml9
-rw-r--r--doc/manual/expressions/simple-building-testing.xml18
4 files changed, 136 insertions, 22 deletions
diff --git a/doc/manual/expressions/builtins.xml b/doc/manual/expressions/builtins.xml
index 6bdfdd55c4b6..eae5f5a029bf 100644
--- a/doc/manual/expressions/builtins.xml
+++ b/doc/manual/expressions/builtins.xml
@@ -32,13 +32,35 @@ available as <function>builtins.derivation</function>.</para>
   <varlistentry><term><function>builtins.add</function>
   <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
 
-    <listitem><para>Return the sum of the integers
+    <listitem><para>Return the sum of the numbers
     <replaceable>e1</replaceable> and
     <replaceable>e2</replaceable>.</para></listitem>
 
   </varlistentry>
 
 
+  <varlistentry><term><function>builtins.all</function>
+  <replaceable>pred</replaceable> <replaceable>list</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if the function
+    <replaceable>pred</replaceable> returns <literal>true</literal>
+    for all elements of <replaceable>list</replaceable>,
+    and <literal>false</literal> otherwise.</para></listitem>
+
+  </varlistentry>
+
+
+  <varlistentry><term><function>builtins.any</function>
+  <replaceable>pred</replaceable> <replaceable>list</replaceable></term>
+
+    <listitem><para>Return <literal>true</literal> if the function
+    <replaceable>pred</replaceable> returns <literal>true</literal>
+    for at least one element of <replaceable>list</replaceable>,
+    and <literal>false</literal> otherwise.</para></listitem>
+
+  </varlistentry>
+
+
   <varlistentry><term><function>builtins.attrNames</function>
   <replaceable>set</replaceable></term>
 
@@ -182,7 +204,7 @@ if builtins ? getEnv then builtins.getEnv "PATH" else ""</programlisting>
   <varlistentry><term><function>builtins.div</function>
   <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
 
-    <listitem><para>Return the quotient of the integers
+    <listitem><para>Return the quotient of the numbers
     <replaceable>e1</replaceable> and
     <replaceable>e2</replaceable>.</para></listitem>
 
@@ -313,6 +335,37 @@ stdenv.mkDerivation {
   </varlistentry>
 
 
+  <varlistentry><term><function>builtins.foldl’</function>
+    <replaceable>op</replaceable> <replaceable>nul</replaceable> <replaceable>list</replaceable></term>
+
+    <listitem><para>Reduce a list by applying a binary operator, from
+    left to right, e.g. <literal>foldl’ op nul [x0 x1 x2 ...] = op (op
+    (op nul x0) x1) x2) ...</literal>. The operator is applied
+    strictly, i.e., its arguments are evaluated first. For example,
+    <literal>foldl’ (x: y: x + y) 0 [1 2 3]</literal> evaluates to
+    6.</para></listitem>
+
+  </varlistentry>
+
+
+  <varlistentry><term><function>builtins.functionArgs</function>
+    <replaceable>f</replaceable></term>
+
+    <listitem><para>
+    Return a set containing the names of the formal arguments expected
+    by the function <replaceable>f</replaceable>.
+    The value of each attribute is a Boolean denoting whether the corresponding
+    argument has a default value.  For instance,
+    <literal>functionArgs ({ x, y ? 123}: ...)  =  { x = false; y = true; }</literal>.
+    </para>
+
+    <para>"Formal argument" here refers to the attributes pattern-matched by
+    the function.  Plain lambdas are not included, e.g.
+    <literal>functionArgs (x: ...)  =  { }</literal>.
+    </para></listitem>
+  </varlistentry>
+
+
   <varlistentry><term><function>builtins.fromJSON</function> <replaceable>e</replaceable></term>
 
     <listitem><para>Convert a JSON string to a Nix
@@ -329,6 +382,24 @@ builtins.fromJSON ''{"x": [1, 2, 3], "y": null}''
   </varlistentry>
 
 
+  <varlistentry><term><function>builtins.genList</function>
+  <replaceable>generator</replaceable> <replaceable>length</replaceable></term>
+
+    <listitem><para>Generate list of size
+    <replaceable>length</replaceable>, with each element
+    <replaceable>i></replaceable> equal to the value returned by
+    <replaceable>generator</replaceable> <literal>i</literal>. For
+    example,
+
+<programlisting>
+builtins.genList (x: x * x) 5
+</programlisting>
+
+    returns the list <literal>[ 0 1 4 9 16 ]</literal>.</para></listitem>
+
+  </varlistentry>
+
+
   <varlistentry><term><function>builtins.getAttr</function>
   <replaceable>s</replaceable> <replaceable>set</replaceable></term>
 
@@ -549,12 +620,12 @@ x: x + 456</programlisting>
   <varlistentry><term><function>builtins.lessThan</function>
   <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
 
-    <listitem><para>Return <literal>true</literal> if the integer
-    <replaceable>e1</replaceable> is less than the integer
+    <listitem><para>Return <literal>true</literal> if the number
+    <replaceable>e1</replaceable> is less than the number
     <replaceable>e2</replaceable>, and <literal>false</literal>
     otherwise.  Evaluation aborts if either
     <replaceable>e1</replaceable> or <replaceable>e2</replaceable>
-    does not evaluate to an integer.</para></listitem>
+    does not evaluate to a number.</para></listitem>
 
   </varlistentry>
 
@@ -605,7 +676,7 @@ map (x: "foo" + x) [ "bar" "bla" "abc" ]</programlisting>
   <varlistentry><term><function>builtins.mul</function>
   <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
 
-    <listitem><para>Return the product of the integers
+    <listitem><para>Return the product of the numbers
     <replaceable>e1</replaceable> and
     <replaceable>e2</replaceable>.</para></listitem>
 
@@ -663,7 +734,7 @@ in config.someSetting</programlisting>
     ./A</literal> will return the set
 
 <programlisting>
-{ A = "regular"; B = "directory"; }</programlisting>
+{ B = "regular"; C = "directory"; }</programlisting>
 
     The possible values for the file type are
     <literal>"regular"</literal>, <literal>"directory"</literal>,
@@ -698,6 +769,23 @@ removeAttrs { x = 1; y = 2; z = 3; } [ "a" "x" "z" ]</programlisting>
   </varlistentry>
 
 
+  <varlistentry><term><function>builtins.replaceStrings</function>
+  <replaceable>from</replaceable> <replaceable>to</replaceable> <replaceable>s</replaceable></term>
+
+    <listitem><para>Given string <replaceable>s</replaceable>, replace
+    every occurrence of the strings in <replaceable>from</replaceable>
+    with the corresponding string in
+    <replaceable>to</replaceable>. For example,
+
+<programlisting>
+builtins.replaceStrings ["oo" "a"] ["a" "i"] "foobar"
+</programlisting>
+
+    evaluates to <literal>"fabir"</literal>.</para></listitem>
+
+  </varlistentry>
+
+
   <varlistentry><term><function>builtins.seq</function>
   <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
 
@@ -709,6 +797,29 @@ removeAttrs { x = 1; y = 2; z = 3; } [ "a" "x" "z" ]</programlisting>
   </varlistentry>
 
 
+  <varlistentry><term><function>builtins.sort</function>
+  <replaceable>comparator</replaceable> <replaceable>list</replaceable></term>
+
+    <listitem><para>Return <replaceable>list</replaceable> in sorted
+    order. It repeatedly calls the function
+    <replaceable>comparator</replaceable> with two elements. The
+    comparator should return <literal>true</literal> if the first
+    element is less than the second, and <literal>false</literal>
+    otherwise. For example,
+
+<programlisting>
+builtins.sort builtins.lessThan [ 483 249 526 147 42 77 ]
+</programlisting>
+
+    produces the list <literal>[ 42 77 147 249 483 526
+    ]</literal>.</para>
+
+    <para>This is a stable sort: it preserves the relative order of
+    elements deemed equal by the comparator.</para></listitem>
+
+  </varlistentry>
+
+
   <varlistentry><term><function>builtins.stringLength</function>
   <replaceable>e</replaceable></term>
 
@@ -722,7 +833,7 @@ removeAttrs { x = 1; y = 2; z = 3; } [ "a" "x" "z" ]</programlisting>
   <varlistentry><term><function>builtins.sub</function>
   <replaceable>e1</replaceable> <replaceable>e2</replaceable></term>
 
-    <listitem><para>Return the difference between the integers
+    <listitem><para>Return the difference between the numbers
     <replaceable>e1</replaceable> and
     <replaceable>e2</replaceable>.</para></listitem>
 
@@ -849,7 +960,7 @@ in foo</programlisting>
   <varlistentry><term><function>builtins.toJSON</function> <replaceable>e</replaceable></term>
 
     <listitem><para>Return a string containing a JSON representation
-    of <replaceable>e</replaceable>.  Strings, integers, booleans,
+    of <replaceable>e</replaceable>.  Strings, integers, floats, booleans,
     nulls and lists are mapped to their JSON equivalents.  Sets
     (except derivations) are represented as objects.  Derivations are
     translated to a JSON string containing the derivation’s output
diff --git a/doc/manual/expressions/derivations.xml b/doc/manual/expressions/derivations.xml
index 90e2786faaab..f2a73dccfe18 100644
--- a/doc/manual/expressions/derivations.xml
+++ b/doc/manual/expressions/derivations.xml
@@ -43,7 +43,7 @@ of which specify the inputs of the build.</para>
 
     <itemizedlist>
 
-      <listitem><para>Strings and integers are just passed
+      <listitem><para>Strings and numbers are just passed
       verbatim.</para></listitem>
 
       <listitem><para>A <emphasis>path</emphasis> (e.g.,
diff --git a/doc/manual/expressions/language-values.xml b/doc/manual/expressions/language-values.xml
index 0bf6632d6e3a..f1174ecb5d8d 100644
--- a/doc/manual/expressions/language-values.xml
+++ b/doc/manual/expressions/language-values.xml
@@ -140,8 +140,13 @@ stdenv.mkDerivation {
 
   </listitem>
 
-  <listitem><para><emphasis>Integers</emphasis>, e.g.,
-  <literal>123</literal>.</para></listitem>
+  <listitem><para>Numbers, which can be <emphasis>integers</emphasis> (like
+  <literal>123</literal>) or <emphasis>floating point</emphasis> (like
+  <literal>123.43</literal> or <literal>.27e13</literal>).</para>
+
+  <para>Numbers are type-compatible: pure integer operations will always
+  return integers, whereas any operation involving at least one floating point
+  number will have a floating point number as a result.</para></listitem>
 
   <listitem><para><emphasis>Paths</emphasis>, e.g.,
   <filename>/bin/sh</filename> or <filename>./builder.sh</filename>.
diff --git a/doc/manual/expressions/simple-building-testing.xml b/doc/manual/expressions/simple-building-testing.xml
index e0dd98b7e67e..bd3901a13351 100644
--- a/doc/manual/expressions/simple-building-testing.xml
+++ b/doc/manual/expressions/simple-building-testing.xml
@@ -7,15 +7,14 @@
 <title>Building and Testing</title>
 
 <para>You can now try to build Hello.  Of course, you could do
-<literal>nix-env -f pkgs/top-level/all-packages.nix -i hello</literal>,
-but you may not want to install a possibly broken package just yet.
-The best way to test the package is by using the command <command
-linkend="sec-nix-build">nix-build</command>, which builds a Nix
-expression and creates a symlink named <filename>result</filename> in
-the current directory:
+<literal>nix-env -i hello</literal>, but you may not want to install a
+possibly broken package just yet.  The best way to test the package is by
+using the command <command linkend="sec-nix-build">nix-build</command>,
+which builds a Nix expression and creates a symlink named
+<filename>result</filename> in the current directory:
 
 <screen>
-$ nix-build pkgs/top-level/all-packages.nix -A hello
+$ nix-build -A hello
 building path `/nix/store/632d2b22514d...-hello-2.1.1'
 hello-2.1.1/
 hello-2.1.1/intl/
@@ -29,8 +28,7 @@ $ ./result/bin/hello
 Hello, world!</screen>
 
 The <link linkend='opt-attr'><option>-A</option></link> option selects
-the <literal>hello</literal> attribute from
-<filename>all-packages.nix</filename>.  This is faster than using the
+the <literal>hello</literal> attribute.  This is faster than using the
 symbolic package name specified by the <literal>name</literal>
 attribute (which also happens to be <literal>hello</literal>) and is
 unambiguous (there can be multiple packages with the symbolic name
@@ -69,7 +67,7 @@ block (or perform other derivations if available) until the build
 finishes:
 
 <screen>
-$ nix-build pkgs/top-level/all-packages.nix -A hello
+$ nix-build -A hello
 waiting for lock on `/nix/store/0h5b7hp8d4hqfrw8igvx97x1xawrjnac-hello-2.1.1x'</screen>
 
 So it is always safe to run multiple instances of Nix in parallel
generated by cgit-pink 1.4.1 (git 2.44.2) at 2024-12-28T16·49+0000