Mark Davis <mark dot davis at icu dash project dot org> wrote:
Although Frank has a point, I think my preferred approach would be to simply define but immediately deprecate subtags like lobjan -- that removes them from the grandfathered list. For the ABNF, we are then only left with the items that are syntactically ill-formed, which we could express with:grandfathered = "i-" irregularI / "sgn-" irregularSgn / irregularOtherirregularI = "ami" / "bnn" / "default" / "enochian" / "hak" / "klingon" / "lux" / "mingo" / "navajo" / "pwn" / "tao" / "tay" / "tsu"irregularSgn= "BE-fr" / "BE-nl" / "CH-de" irregularOther = "en-GB-oed"We then have the smallest ABNF that (with the exception of duplicate singletons), describes the well-formed cases without letting anything else in.
I think creating more deprecated-at-birth subtags is a terrible idea. As you showed, it doesn't even simplify the ABNF -- you still have the messy "irregularOther" production. It reduces the size of the list in the ABNF, but increases the amount of trash in the Registry.
The ABNF can't cover every possible syntactical tagging rule anyway; consider en-b-bbb-a-aaa.
-- Doug Ewell Fullerton, California, USA http://users.adelphia.net/~dewell/ RFC 4645 * UTN #14 _______________________________________________ Ltru mailing list Ltru at ietf.org https://www1.ietf.org/mailman/listinfo/ltru
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