- From: Julian Reschke <julian.reschke@gmx.de>
- Date: Wed, 02 Aug 2006 10:28:35 +0200
- To: Ian Hickson <ian@hixie.ch>
- CC: Bjoern Hoehrmann <derhoermi@gmx.net>, public-webapi@w3.org
Ian Hickson schrieb: > On Wed, 2 Aug 2006, Julian Reschke wrote: >> If compatibility to existing code (which doesn't check for null) is the >> driver here, then please consider adding a new method such as >> "isHeaderPresent(headername)". > > Purely out of interest, could you give the use case? Only for a related problem: early versions of the WebDAV REDIRECTREF extension defined a header like that (<http://greenbytes.de/tech/webdav/draft-ietf-webdav-redirectref-protocol-06.html#rfc.section.11.2>). It was subsequently changed because it couldn't be used with Microsoft's XmlHttpRequest object. I wouldn't be surprised if similar headers have been defined by others (but possibly not published through the IETF process). Speaking of which, it might be good if <http://www.w3.org/TR/XMLHttpRequest/#dfn-setrequestheader> would clarify that setting a request header to "" is legal, and that the header really MUST be set to that value. Finally, looking at the current text over there: "# Nothing MUST be done if the header or value arguments contain any U+000A LINE FEED or U+000D CARRIAGE RETURN characters, or if the header argument contains any U+0020 SPACE or U+003A COLON charecters. # Nothing MUST be done if the header argument matches Accept-Charset, Accept-Encoding, Content-Length, Expect, Date, Host, Keep-Alive, Referer, TE, Trailer, Transfer-Encoding or Upgrade case-insensitively." This is extremely misleading. "Nothing MUST be done..." essentially means that everything is optional here. I think what it intends to say is something like... "The header MUST NOT be changed if....". Best regards, Julian
Received on Wednesday, 2 August 2006 08:28:46 UTC