Help:Bad title

Some page titles are defined as bad for various reasons. You can't create pages with these titles.

For details of what constitutes a bad title, see regex section.

For reference here is an example of a horrible, but valid title:

• Some¬`!"£$^&*()_+-=~?/.,;:'@

Things you can't use in titles:

• The following standard CGI chars are not good:
  • http://www.mediawiki.org/wiki/Some%s - Very bad!

• The following standard wiki syntax seems to work:
  • http://www.mediawiki.org/wiki/Some%sSome[s - gets trimmed
  • http://www.mediawiki.org/wiki/Some%sSome]s - gets trimmed
  • http://www.mediawiki.org/wiki/Some%sSome{s - bad
  • http://www.mediawiki.org/wiki/Some%sSome}s - bad

• and some just don't work:
  • http://www.mediawiki.org/wiki/Some%sSome#s - gets trimmed

• and some HTML like constructs are very bad, and can't be show here because they break page formatting:
  • http://www.mediawiki.org/wiki/Some%sSome<s - bad
  • http://www.mediawiki.org/wiki/Some%sSome>s - bad

HTTP Codes

These vary according to the version number of the software:

• 400 (Bad Request) for v1.19.1 and above
• 200 (OK) for v1.16.4 and earlier

Regex

# Matching titles will be held as illegal.
$rxTc = '/' .
       # Any character not allowed is forbidden...
       '[^' . self::legalChars() . ']' .
       # URL percent encoding sequences interfere with the ability
       # to round-trip titles -- you can't link to them consistently.
       '|%[0-9A-Fa-f]{2}' .
       # XML/HTML character references produce similar issues.
       '|&[A-Za-z0-9\x80-\xff]+;' .
       '|&#[0-9]+;' .
       '|&#x[0-9A-Fa-f]+;' .
       '/S';

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