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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> |