Fix typos in the Nix Manual.

doc/manual/command-ref/conf-file.xml

@@ -433,7 +433,7 @@ builtins.fetchurl {
   <varlistentry xml:id="conf-keep-env-derivations"><term><literal>keep-env-derivations</literal></term>
 
     <listitem><para>If <literal>false</literal> (default), derivations
-    are not stored in Nix user environments.  That is, the derivation
+    are not stored in Nix user environments.  That is, the derivations of
     any build-time-only dependencies may be garbage-collected.</para>
 
     <para>If <literal>true</literal>, when you add a Nix derivation to

doc/manual/command-ref/nix-env.xml

@@ -659,7 +659,7 @@ upgrading `mozilla-1.2' to `mozilla-1.4'</screen>
 <literal>gcc-3.3.1</literal> are split into two parts: the package
 name (<literal>gcc</literal>), and the version
 (<literal>3.3.1</literal>).  The version part starts after the first
-dash not following by a letter.  <varname>x</varname> is considered an
+dash not followed by a letter.  <varname>x</varname> is considered an
 upgrade of <varname>y</varname> if their package names match, and the
 version of <varname>y</varname> is higher that that of
 <varname>x</varname>.</para>

doc/manual/command-ref/nix-prefetch-url.xml

@@ -53,7 +53,7 @@ avoided.</para>
 <para>If <replaceable>hash</replaceable> is specified, then a download
 is not performed if the Nix store already contains a file with the
 same hash and base name.  Otherwise, the file is downloaded, and an
-error if signaled if the actual hash of the file does not match the
+error is signaled if the actual hash of the file does not match the
 specified hash.</para>
 
 <para>This command prints the hash on standard output.  Additionally,

doc/manual/expressions/builtins.xml

@@ -289,7 +289,7 @@ if builtins ? getEnv then builtins.getEnv "PATH" else ""</programlisting>
 
     <listitem><para>Return element <replaceable>n</replaceable> from
     the list <replaceable>xs</replaceable>.  Elements are counted
-    starting from 0.  A fatal error occurs in the index is out of
+    starting from 0.  A fatal error occurs if the index is out of
     bounds.</para></listitem>
 
   </varlistentry>
@@ -1466,7 +1466,7 @@ in foo</programlisting>
       <listitem><para>A set containing <literal>{ __toString = self: ...; }</literal>.</para></listitem>
       <listitem><para>An integer.</para></listitem>
       <listitem><para>A list, in which case the string representations of its elements are joined with spaces.</para></listitem>
-      <listitem><para>A Boolean (<literal>false</literal> yields <literal>""</literal>, <literal>true</literal> yields <literal>"1"</literal>.</para></listitem>
+      <listitem><para>A Boolean (<literal>false</literal> yields <literal>""</literal>, <literal>true</literal> yields <literal>"1"</literal>).</para></listitem>
       <listitem><para><literal>null</literal>, which yields the empty string.</para></listitem>
     </itemizedlist>
     </listitem>

doc/manual/expressions/simple-building-testing.xml

@@ -43,7 +43,7 @@ use <command>nix-build</command>’s <option
 linkend='opt-out-link'>-o</option> switch to give the symlink another
 name.</para>
 
-<para>Nix has a transactional semantics.  Once a build finishes
+<para>Nix has transactional semantics.  Once a build finishes
 successfully, Nix makes a note of this in its database: it registers
 that the path denoted by <envar>out</envar> is now
 <quote>valid</quote>.  If you try to build the derivation again, Nix