diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/manual/builtins.xml | 14 | ||||
| -rw-r--r-- | doc/manual/opt-common.xml | 4 |
2 files changed, 4 insertions, 14 deletions
diff --git a/doc/manual/builtins.xml b/doc/manual/builtins.xml index 1f881a911..3eee36f2a 100644 --- a/doc/manual/builtins.xml +++ b/doc/manual/builtins.xml @@ -77,18 +77,8 @@ attrValues = attrs: map (name: builtins.getAttr name attrs) (builtins.attrNames if builtins ? getEnv then builtins.getEnv "PATH" else ""</programlisting> This allows a Nix expression to fall back gracefully on older Nix - installations that don’t have the desired built-in function. - However, in that case you should not write - -<programlisting> -if builtins ? getEnv then __getEnv "PATH" else ""</programlisting> - - This Nix expression will trigger an “undefined variable” error on - older Nix versions since <function>__getEnv</function> doesn’t - exist. <literal>builtins.getEnv</literal>, on the other hand, is - safe since <literal>builtins</literal> always exists and attribute - selection is lazy, so it’s only performed if the test - succeeds.</para></listitem> + installations that don’t have the desired built-in + function.</para></listitem> </varlistentry> diff --git a/doc/manual/opt-common.xml b/doc/manual/opt-common.xml index 316ad6658..ac967e23d 100644 --- a/doc/manual/opt-common.xml +++ b/doc/manual/opt-common.xml @@ -251,14 +251,14 @@ <programlisting> { # The system (e.g., `i686-linux') for which to build the packages. - system ? __currentSystem + system ? builtins.currentSystem <replaceable>...</replaceable> }: <replaceable>...</replaceable></programlisting> So if you call this Nix expression (e.g., when you do <literal>nix-env -i <replaceable>pkgname</replaceable></literal>), the function will be called automatically using the value <link - linkend='builtin-currentSystem'><literal>__currentSystem</literal></link> + linkend='builtin-currentSystem'><literal>builtins.currentSystem</literal></link> for the <literal>system</literal> argument. You can override this using <option>--arg</option>, e.g., <literal>nix-env -i <replaceable>pkgname</replaceable> --arg system |