Subject: Re: [Slim] Primary language tags (was "Re: draft-tomkinson comments")

From: "Doug Ewell" <[email-masked]>
Date: Mon, 02 Nov 2015 16:12:15 -0700

Randall Gellens wrote:

>> The same reasoning enable us to distinguish
>> written from spoken language by using the
>> Script subtag to indicate written, even if
>> Suppress-Script is registered for the language
>> tag.
>
> [...]
>
> I am concerned that overloading the use of
> 'script' in this way is dangerous, and further, I
> am not convinced that we need to differentiate
> written from spoken language. If it turns out
> that we do, we should choose a different
> mechanism where that is the only meaning.

I agree. Although a script subtag does identify the script in which the
tagged content is written -- implying that the content is indeed written
-- BCP 47 does not state anywhere that a script subtag should be used to
distinguish written content from content in other modalities, and for
good reason. Identification of modality, like many other attributes of
linguistic content, is out of scope for BCP 47. The draft should define
a protocol that uses BCP 47, not seek to extend it.

Furthermore, encouraging the use of script subtags even in the presence
of Suppress-Script, without good reason to override (such as when
identifying French written in Cyrillic letters), runs counter to the
general principle of avoiding unnecessary subtags -- although I agree
with Addison that the draft may go too far beyond BCP 47 in discouraging
potentially necessary subtags.

--
Doug Ewell | http://ewellic.org | Thornton, CO 🇺🇸

---

From: Gunnar Hellström <[email-masked]>
Date: Tue, 3 Nov 2015 08:07:16 +0100

> potentially necessary subtags.
OK, let us add the distinguishing of modalities to BCP 47 in an 
acceptable way then.
This seems to be needed for both slim drafts.
Neither m= media types in SDP nor Content-Types in e-mail are consistent 
enough to tell if the content will be spoken, written or signed.
Sign languages are well identified in BCP 47, but not written versus spoken.

Examples of when the sdp types or Content-Types are not specific:

Text overlay on video  versus the image of a speaking person.
The m=message media type for MSRP can contain text or audio or video 
messages
A number of application types can have combined media, e.g. mp4
The draft-sdpneg data channel for WebRTC can contain a number of 
subchannels, one of them being text, but identified by a subprotocol 
name. WebRTC can be controlled by SIP, so it would be in scope to 
negotiate language and modality also for this form of WebRTC with slim.

How would the difference between spoken and written best be expressed in 
an extended BCP47?

/Gunnar