Versioning Language Features in JScript

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Versioning Language Features in JScript | ASP NET Hosting — Fri, 17 Apr 2009 02:32:05 GMT

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JScript Blog : Versioning Language Features in JScript

DotNetShoutout — Fri, 17 Apr 2009 17:02:09 GMT

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re: Versioning Language Features in JScript

Stoyan — Sat, 18 Apr 2009 12:35:56 GMT

I find this.JSON is not very robust change too easy to fail if I forget var anywhere in the code

mby something more verbose?

if (typeof JSON === "object" && typeof JSON.encode === "function"){

}

re: Versioning Language Features in JScript

OMFG — Tue, 21 Apr 2009 15:40:23 GMT

Are you seriously out to lunch?! or did you fail to clarify that this DOES NOT apply to normal IE web browser development?

if in IE8 I need to check/set variables:

SCRIPTLANGUAGEVERSION_5_7

SCRIPTLANGUAGEVERSION_5_8

In order to get/not get method availability in ===> JAVASCRIPT <===

Then this plan is seriously mega-flawed.

the language attribute on script tags is already deprecated because IE !@#$ed it up in earlier versions so we no longer do stuff like:

Please clarify that developers DO NOT NEED TO SET ANYTHING to get the MAXIMUM JavaScript implementation that IE8 supports.

If you can't, please jump on the IE Blog and disclose this disaster to the developers that will be affected by this and start ducking when they start throwing the furniture.

OMFG!

re: Versioning Language Features in JScript

Smith — Tue, 21 Apr 2009 20:34:38 GMT

OMFG,

I think you are mistaken. The usage of IActiveScriptProperty::SetProperty is in my opinion for other JSCript hosts like WScript, CScript etc. For IE8, the feature is aligned with whether you are running your sire in standards mode or not which makes sense to me at least. IE8 standards mode is to enable IE run as a browser which is more compatible with standards. So running the new JScript compliant feature in a different/default would break this.

However I would like to hear what happens if I call IActiveScriptProperty::SetProperty from JScript running within the browser (IE).

Thanks,

Smith

re: Versioning Language Features in JScript

GauravS — Wed, 22 Apr 2009 02:29:44 GMT

@OMFG: Smith’s reasoning is correct. The JScript language features are tied to the document mode chosen by a web page. If the document mode is “IE8 Standards”, all the nine features mentioned above are switched on. For all other document modes, these features are not available (equates to language support as it existed in IE7).

One of the ways in which a web developer can choose to use the IE8 Standards mode (and get the most of the JScript language changes) is by using the X-UA-Compatible meta tag <meta http-equiv="X-UA-Compatible" content="IE=IE8"> as described in http://msdn.microsoft.com/en-us/library/cc288325(VS.85).aspx.

The SCRIPTLANGUAGEVERSION flags are not for use by web developers. They are meant for developers creating new JScript hosts by using the IActiveScript interfaces (like developers creating a browser, WScript host etc.)

@Smith: From versioning perspective, calling IActiveScriptProperty::SetProperty from JScript running within the browser (IE) is not a supported scenario. It will not impact the language support chosen by the page (which is based on the document mode) and cannot be used to switch between the different support levels.

re: Versioning Language Features in JScript

AndyE — Tue, 28 Apr 2009 14:52:43 GMT

So there's no way of activating the new JScript features without enabling IE8 standards mode for the DOM?

That seems pretty poor if you're a Windows Desktop Gadget developer - using the new JScript features is impossible without risking backwards compatibility with IE7 users.

It seems like Gadget design is going the way of the web design - we can't adopt new standards until years after they appear when IE7 market share drops to below 5%/10%

re: Versioning Language Features in JScript

Mitch 74 — Wed, 29 Apr 2009 18:19:10 GMT

@AndyE: you can still use the software-only implementation of the JSON object - which would allow your gadget to work with "native" IE6 and IE7 too.

re: Versioning Language Features in JScript

CB — Thu, 14 May 2009 11:28:46 GMT

Why won't you support the latest scripting and html features in your releases ? You are always behind competitors for absolutely no good reason.

Where is for example the HTML5 support for things like <CANVAS> currently supported (for a long time) by Firefox and Chrome.

Is it because you fear nobody would use Silverlight if there was an easy browser independent way to do animations and video without plugins ??

SVG support is aboslutely not the same thing since it isn't even fully scriptable.

And why did we need to wait until IE8 to get standards support ?? Amazing.

You need to lead the development, not lagg behind competitors all the time !!!

re: Versioning Language Features in JScript

warrens — Fri, 15 May 2009 00:22:08 GMT

CB, I realise it's "cool" to complain anonymously on the Internet. But, try and be reasonable.

Yes, CSS3, HTML5 and SVG are important, but Microsoft has taken the right path so far with fixing the much more widely-used CSS 2.1 standard first, before moving on to the emerging standards.

It's what they told us they were going to do, and it's what they've delivered: IE8 actually has a more complete implementation of CSS 2.1 than Firefox and Opera. One of the big standards-testing web sites measures IE8's CSS 2.1 compatibility at 99%... the other browsers are in the low-90s, mainly due to broken / incomplete implementations of CSS 2.1 pseudo-elements and at-elements.

http://www.webdevout.net/browser-support-summary?IE7=on&IE8=on&FX2=on&FX3=on&OP9=on&SF2=on&uas=CUSTOM

You might as well be asking why we're still waiting for Firefox to get "standards support", especially considering they've been saying they've had it for years.

re: Versioning Language Features in JScript

-TNO- — Wed, 27 May 2009 00:05:17 GMT

Maybe I'm just ignorant, but is there a better example on how to enable the new JScript version in WSH/ASP? A registry setting perhaps? The example given doesn't quite lend itself to web developers and system administrators seeking to use these new features.

re: Versioning Language Features in JScript

GauravS — Thu, 28 May 2009 03:49:54 GMT

@TNO: These new language features are currently not supported/versioned by hosts other than Internet Explorer. Hosts other than IE such as WSH/ASP will automatically use the latest vesrion of JScript installed on the machine. However, the language feature support is equivalent to that of JScript v5.7.

re: Versioning Language Features in JScript

Neiyuki — Sat, 06 Jun 2009 09:53:43 GMT

Is there any way to enable the 5.8 features in WSH?

Or will you going to change the WSH executables?

re: Versioning Language Features in JScript

GauravS (MSFT) — Mon, 22 Jun 2009 19:21:12 GMT

@Neiyuki: The WSH currently does not support the 5.8 features. However, you can use script based work-arounds for some of the 5.8 features like JSON.

re: Versioning Language Features in JScript

John — Fri, 07 Aug 2009 02:24:44 GMT

@GauravS: There is a growing demand for being able to use these new features in hosts other than IE, such as WSH/ASP. Is there any reason why there is no option to select the 5.8 feature set for these hosts?

Could a method for selecting a version be provided? Possibly a Registry setting, or better still:

ScriptEngine.set('5.8');

re: Versioning Language Features in JScript

GauravS — Fri, 07 Aug 2009 20:33:44 GMT

@John: Due to the possible side-effects, there is no simple mechanism which can enable these features unless the host makes a change to enable the new feature-set.

If the feature you are looking at is JSON support, you can use the JSON imlementation from www.JSON.org as a workaround.

re: Versioning Language Features in JScript

John — Fri, 07 Aug 2009 22:44:17 GMT

@GauravS: What sort of side-effects are you referring to? Things could work in exactly the same manner as IE8, the developer opts-in. As far as I am aware the whole point of the IE8 "opt-in" was to avoid side-effects.

Surely the JScript feature set could provide a script based opt-in such as:

ScriptEngine.set('5.8');

What would be the problem in implementing such a feature in a future revision?

Server-side JavaScript is gaining momentum and Microsoft has an excellent platform for this in ASP 3.0. It seems wrong using script based JSON implementations when the native feature is there, just no way to access it.

Thanks,

John

re: Versioning Language Features in JScript

GauravS — Sat, 08 Aug 2009 00:09:14 GMT

@John: I was referring to the use of registry keys to switch versions. No such support is available.

Thanks for your feedback! Will consider the approach you suggest for the future versions.

re: Versioning Language Features in JScript

Sergei — Sat, 08 Aug 2009 07:45:43 GMT

Are you saying the side effect is registry keys? I was thinking side effect meant something in functionality. And why only registry key to switch version? You can as well do it at runtime. Can you tell us why other hosts apart from IE cannot do this switch at runtime. I understand the IActive* way of integrating with JavaScript, but I cannot understand why one host can do it from native code while others can't and need registry settings to do the same? Can you explain please.

Thanks.

re: Versioning Language Features in JScript

John — Sat, 08 Aug 2009 18:38:28 GMT

@Sergei: I was under the same impression, that the side-effects were to do with the functionality being exposed to other hosts, however, this doesn't seem to be the case. There aren't any registry keys to enable the hidden functionality, I had just suggested it. Obviously a registry setting would be a less than ideal solution.

@GauravS: If there aren't any side-effects related to exposing the hidden functionality, then I really can't understand why a script based method isn't provided to switch between engines? This would provide much more flexibility to the developer whilst also making it host independent. I would imagine that it would be a trivial thing to implement?

I appreciate your comment on considering this for a future release, if this type of thing isn't implemented, then any new features that are added will again be inaccessible which would be a real shame.

Hopefully you could push this through sooner rather than later, and we could all enjoy the hard work the JScript team has done in bringing us these new features.

Thanks,

John

re: Versioning Language Features in JScript

Nigel — Fri, 04 Dec 2009 04:42:15 GMT

So, how do you actually set IActiveScriptProperty::SetProperty for WSF script?