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+# Generators {#sec-generators}
+Generators are functions that create file formats from nix data structures, e. g. for configuration files. There are generators available for: `INI`, `JSON` and `YAML`
+
+All generators follow a similar call interface: `generatorName configFunctions data`, where `configFunctions` 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 `mkSectionName ? (name: libStr.escape [ "[" "]" ] name)` from the `INI` generator. It receives the name of a section and sanitizes it. The default `mkSectionName` escapes `[` and `]` with a backslash.
+
+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 `: ` as separator, the strings `"yes"`/`"no"` as boolean values and requires all string values to be quoted:
+
+```nix
+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 ''"${v}"''
+        # and delegats all other values to the default generator
+        else generators.mkValueStringDefault {} v;
+    } ":";
+  };
+
+# the INI file can now be given as plain old nix values
+in customToINI {
+  main = {
+    pushinfo = true;
+    autopush = false;
+    host = "localhost";
+    port = 42;
+  };
+  mergetool = {
+    merge = "diff3";
+  };
+}
+```
+
+This will produce the following INI file as nix string:
+
+```INI
+[main]
+autopush:"no"
+host:"localhost"
+port:42
+pushinfo:"yes"
+str\:ange:"very::strange"
+
+[mergetool]
+merge:"diff3"
+```
+
+::: {.note}
+Nix store paths can be converted to strings by enclosing a derivation attribute like so: `"${drv}"`.
+:::
+
+Detailed documentation for each generator can be found in `lib/generators.nix`.