[Webkit-unassigned] [Bug 67537] Implement a ProgressEvent constructor for JSC

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=67537





--- Comment #7 from Kentaro Hara <haraken at google.com>  2011-09-06 17:35:06 PST ---
(In reply to comment #6)
> Yes, you can only represent unsigned long long values in the range [0, 2**53-1] exactly in JS.  Your test could validly assert that 18446744073709551615 comes out as 18446744073709552000.  (Well, I didn't check that second number but I assume it's the closest integral double to 2**64-1.)
> 
> We discussed introducing a 53-bit integer type in Web IDL at one point, but it never got added in the end.

Thank you, I found the spec (http://www.w3.org/TR/WebIDL/#es-unsigned-long-long). According to the spec, "new ProgressEvent("foo", {loaded: 18446744073709551615}).loaded" should be 0, because 18446744073709551615 is represented as 18446744073709551616.0 in double, and modulo(18446744073709551616, 2^64) becomes 0.

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.