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Seredipity default event_s9ymarkup plugin breaking URLs that contain underscores


The default Serendipity mark-up plugin (event_s9ymarkup) currently breaks URLs that contain underscores.


will end up</u>%26_Waldorf

because of a faulty regex. Garvin Hicking does not really want to fix this. (See this s9y support forum article for arguments pro/contra fixing it). So if you encounter this problem, your options are:

  • replace _ in URLs with %5F (aka manually urlencode it)
  • remove the plugin or disable it
  • patch the plugin

Patching is basically changing


$text = preg_replace('/\b_([\S ]+?)_\b/','<u>\1</u>',$text);


$text = preg_replace('/\ _([\S ]+?)_\ /',' <u>\1</u> ',$text);

If you want to be writing things like "Haha[lol]" (which I have no real use for ...), extend the "\ " with whatever you'd like to be o.k. to delimit bolded words beyond blanks. It should only be symbols that are not valid in URLs (so none of "$-_.+!*'()," which are all valid in URLs according to RFC 1738).

You may also want to consider replacing one underscore ("_") with two or more ("__") to make the detection, that you actually wanted to write bold text, more reliable.