Proposed new variant subtag: pre1917

Philip Newton philip.newton at
Wed Sep 15 16:13:06 CEST 2010

On Wed, Sep 15, 2010 at 15:46, Doug Ewell <doug at> wrote:
> Philip Newton <philip dot newton at gmail dot com> wrote:
>> Remember that variant subtags may not be longer than eight characters;
>> also, if they start with a digit, they must be followed by precisely
>> three characters for a total length of four characters (and if they
>> start with a letter, they must be followed by at least four characters
>> for a minimum length of five characters).
> This is a common misreading of the ABNF for variant subtags:
> variant       = 5*8alphanum         ; registered variants
>              / (DIGIT 3alphanum)
> The first production -- 5*8 alphanum -- means that subtags 5 to 8
> [characters] in length can begin with either a letter or a digit.  So
> whatever its other advantages or disadvantages might be, '1918orth' is
> just as valid syntactically as 'orth1918'.

That makes sense, now that you've pointed it out to me. Thank you for
the correction and clarification.

Philip Newton <philip.newton at>

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