placeholders in settings.php?

[Klap-in]

I observe regularly authors use php code in the settings strings in settings.php. In the strings in lang.php they can use sprintf() with %s etc as placeholders. Is it worth to consider something like that for settings? how?

• Via placeholders in the string: as submissions are submitted via the Tool, it is probably too easy to suggest wrong alternatives (i.e. names of other config settings). (however, it is all html, so that impose also a bit such a risk).

• Or add a metadata setting that allows configuring the replacements. Not sure if it easy to propose there php variables, for some cases it might be executed too early ($lang['..']).

• ...?

Examples:

A path with php:

$lang['confhowhardstyle'] = 'Choose image :<br>1 : <img src="'.DOKU_BASE.'lib/plugins/howhard/images/style1/3.png"><br>2 : <img src="'.DOKU_BASE.'lib/plugins/howhard/images/style2/3.png"><br><br>3 : <img src="'.DOKU_BASE.'lib/plugins/howhard/images/style3/3.png"><br><br>4 : <img src="'.DOKU_BASE.'lib/plugins/howhard/images/style4/3.png">';

References to other settings:

$lang['index_priority'] = "Priority order of pages used as index pages, between start, inside and outside. Exemple with the namespace foo:bar: start= foo:bar:".$conf['start']." ; outside= foo:bar ; inside= foo:bar:bar";

Reference to other strings:

$lang['missing_mmdb_warning'] = "<br />To install GeoLite2-City.mmdb, go to the quickstats admin page and click the <b>" . $lang['btn_download'] . " </b> Button";

Config plugin code:
https://github.com/dokuwiki/dokuwiki/blob/11f4950ced97a3542fb13bd54b2e57521f1fa62c/lib/plugins/config/admin.php#L127

https://github.com/dokuwiki/dokuwiki/blob/11f4950ced97a3542fb13bd54b2e57521f1fa62c/lib/plugins/config/core/Setting/Setting.php#L213

https://github.com/dokuwiki/dokuwiki/blob/11f4950ced97a3542fb13bd54b2e57521f1fa62c/lib/plugins/config/core/Setting/Setting.php#L274-L279