uri_normalize

%<!-- -->-decodes any "unreserved" characters (or characters in unescape_extra) in part, and %<!-- -- >-encodes any non-ASCII characters, spaces, and non-printing characters in part.

"Unreserved" characters are those that are not allowed to be used for punctuation according to the URI spec. For example, letters are unreserved, so uri_normalize will turn <literal>http://example.com/foo/b%<!-- -->61r</literal > into <literal>http://example.com/foo/bar</literal>, which is guaranteed to mean the same thing. However, "/" is "reserved", so <literal>http://example.com/foo%<!-- -->2Fbar</literal> would not be changed, because it might mean something different to the server.

In the past, this would return null if part contained invalid percent-encoding, but now it just ignores the problem (as URI already did).

Parameters:

part	a URI part
unescape_extra	reserved characters to unescape (or null)

Returns:

the normalized URI part