Lets not forget about XML.

XML::Simple makes for an excellent app config also. 

app.rc:

<app>
  <db>
    <username>Python</username>
    <password>sucks</password>
  </db>
  <backup>
     <machine>guido</machine>
     <frequency>4 hours</frequency>
  </backup>
  <logging>
     <file>/var/log/applog</file>
     <level>2</level>
  </logging>
</app>

[download]

Derives the same access: 

$app->{'db'}->{'username'}

[download]
As well as all the good stuff that comes with xml, such as for checking the "config" file ( actually just another xml doc ), for well-formedness and validity. Also, XML will provide ties for easy config-file update and modification via the application itself, should you choose to use something like XML::Writer. A fun and nice way of getting fancy for say, a web editable/creatable configuration file.

In reply to RE: What are all the means of application configuration? by Zarathustra
in thread What are all the means of application configuration? by princepawn

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