Re: [XHR]

Jakub Łopuszański <qbolec@gmail.com> skreiv Sat, 06 Oct 2012 18:09:16 +0200

> Spec at http://www.w3.org/TR/XMLHttpRequest/ says that:
> 1. each change of state must fire an event
> 2. readyState must always be equal to the current state
> it follows that it is possible for eventhandler to be called more than  
> once with the same value of readyState

You mean a race condition of sorts where the implementation fires an event  
for the change from readyState 2 to readyState 3 but when the event gets  
fired, readyState turns out to be 4 already? An implementation doing that  
is not likely to be web-compatible, so if the spec text seems to allow  
this we should probably fix it. (There was however at least one  
implementation that supported a sort of server-push mode by supporting  
chunked HTTP and firing a new readyState 3 event every time a new part of  
the content came in - I think Firefox used to do this but I'm not sure if  
they still do.) So I don't know if we really want to outlaw firing several  
events for the same readyState value..


-- 
Hallvord R. M. Steen
Core tester, Opera Software

Received on Monday, 8 October 2012 08:44:51 UTC