On 20/11/2010, at 11:07, RobG wrote: > On Nov 19, 7:55 pm, Jorge Chamorro <[email protected]> wrote: >> On 18/11/2010, at 00:46, RobG wrote: >> >>> ... window is a host object ... >> >> Please stop spreading FUD. Seehttp://www.w3.org/TR/Window/ >> >> "This specification defines the Window object, which provides the global >> namespace for web scripting languages" > > The W3C does not define language features of ECMAScript, ECMA does. > Never the less, the window object described above is, by the > definition provided in the ECMAScript Language Specification, a host > object. > > "...an ECMAScript program will provide not only the objects and other > facilities described in this specification but also certain > environment-specific host objects, whose description and behaviour are > beyond the scope of this specification..." > > ECMA-262 ed 3, section 4. > > And in section 11.4.3 is states that the value returned by a typeof > test on a host object is implementation-dependent.
That would be the case if it were not for the fact that window === globalObject, and global object is *not* a host object. Both the ECMA spec and the w3c point out that window === globalObject in browsers. And that's what all browser makers are doing, except Microsoft. >> c.l.js.-itis ? > > No. I was pointing out that the value that a host object or property > may return for a typeof test is *defined* in the relevant standard as > being implementation dependent (that is, the author of that > environment can do whatever they want). There is nowhere in any W3C > standard that says what value a typeof test on DOM objects (which are > all host objects) should return. Further, it is trivial to discover > inconsistent results across browsers for a great many objects and > properties. > > So basing a feature test solely on the result of a typeof test on a > host object is certain to be unreliable. In IEs, yes. In any other current -decent- browser, no. -- Jorge. -- You received this message because you are subscribed to the Google Groups "iPhoneWebDev" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/iphonewebdev?hl=en.
