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nixos: update default cases from KDM/KDE4 to SDDM/KDE5

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This commit is contained in:
Graham Christensen
2017-02-09 21:52:00 -05:00
parent 4000489266
commit b12564cc1b
12 changed files with 43 additions and 54 deletions
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nixos/doc/manual/development/option-declarations.xml
+24 -24
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@@ -65,22 +65,22 @@ options = {
</para>
<section xml:id="sec-option-declarations-eot"><title>Extensible Option
<section xml:id="sec-option-declarations-eot"><title>Extensible Option
Types</title>
<para>Extensible option types is a feature that allow to extend certain types
<para>Extensible option types is a feature that allow to extend certain types
declaration through multiple module files.
This feature only work with a restricted set of types, namely
This feature only work with a restricted set of types, namely
<literal>enum</literal> and <literal>submodules</literal> and any composed
forms of them.</para>
<para>Extensible option types can be used for <literal>enum</literal> options
that affects multiple modules, or as an alternative to related
<para>Extensible option types can be used for <literal>enum</literal> options
that affects multiple modules, or as an alternative to related
<literal>enable</literal> options.</para>
<para>As an example, we will take the case of display managers. There is a
central display manager module for generic display manager options and a
module file per display manager backend (slim, kdm, gdm ...).
module file per display manager backend (slim, sddm, gdm ...).
</para>
<para>There are two approach to this module structure:
@@ -96,7 +96,7 @@ options = {
</para>
<para>Both approachs have problems.</para>
<para>Making backends independent can quickly become hard to manage. For
display managers, there can be only one enabled at a time, but the type
system can not enforce this restriction as there is no relation between
@@ -108,18 +108,18 @@ options = {
central module will require to change the central module option every time
a new backend is added or removed.</para>
<para>By using extensible option types, it is possible to create a placeholder
option in the central module (<xref linkend='ex-option-declaration-eot-service'
/>), and to extend it in each backend module (<xref
linkend='ex-option-declaration-eot-backend-slim' />, <xref
linkend='ex-option-declaration-eot-backend-kdm' />).</para>
<para>By using extensible option types, it is possible to create a placeholder
option in the central module (<xref linkend='ex-option-declaration-eot-service'
/>), and to extend it in each backend module (<xref
linkend='ex-option-declaration-eot-backend-slim' />, <xref
linkend='ex-option-declaration-eot-backend-sddm' />).</para>
<para>As a result, <literal>displayManager.enable</literal> option values can
be added without changing the main service module file and the type system
automatically enforce that there can only be a single display manager
enabled.</para>
<example xml:id='ex-option-declaration-eot-service'><title>Extensible type
<example xml:id='ex-option-declaration-eot-service'><title>Extensible type
placeholder in the service module</title>
<screen>
services.xserver.displayManager.enable = mkOption {
@@ -127,29 +127,29 @@ services.xserver.displayManager.enable = mkOption {
type = with types; nullOr (enum [ ]);
};</screen></example>
<example xml:id='ex-option-declaration-eot-backend-slim'><title>Extending
<literal>services.xserver.displayManager.enable</literal> in the
<example xml:id='ex-option-declaration-eot-backend-slim'><title>Extending
<literal>services.xserver.displayManager.enable</literal> in the
<literal>slim</literal> module</title>
<screen>
services.xserver.displayManager.enable = mkOption {
type = with types; nullOr (enum [ "slim" ]);
};</screen></example>
<example xml:id='ex-option-declaration-eot-backend-kdm'><title>Extending
<literal>services.foo.backend</literal> in the <literal>kdm</literal>
<example xml:id='ex-option-declaration-eot-backend-sdm'><title>Extending
<literal>services.foo.backend</literal> in the <literal>sdm</literal>
module</title>
<screen>
services.xserver.displayManager.enable = mkOption {
type = with types; nullOr (enum [ "kdm" ]);
type = with types; nullOr (enum [ "sddm" ]);
};</screen></example>
<para>The placeholder declaration is a standard <literal>mkOption</literal>
declaration, but it is important that extensible option declarations only use
<para>The placeholder declaration is a standard <literal>mkOption</literal>
declaration, but it is important that extensible option declarations only use
the <literal>type</literal> argument.</para>
<para>Extensible option types work with any of the composed variants of
<literal>enum</literal> such as
<literal>with types; nullOr (enum [ "foo" "bar" ])</literal>
<para>Extensible option types work with any of the composed variants of
<literal>enum</literal> such as
<literal>with types; nullOr (enum [ "foo" "bar" ])</literal>
or <literal>with types; listOf (enum [ "foo" "bar" ])</literal>.</para>
</section>