Re: Multiple header fields with the same field name - unwritten assumption about quoted commas in values?

[Zhong Yu <[e-mail]>]

On Tue, Jan 15, 2013 at 6:21 AM, Julian Reschke <[e-mail]> wrote:
> On 2013-01-15 12:47, Piotr Dobrogost wrote:
>>
>> To summarize, from the point of view of http client library (see
>> https://github.com/kennethreitz/requests/issues/741):
>>
>> - The safe approach is to not merge any header fields with the same field
>> name.
>
>
> Yes.
>
>
>> - If merging, merge only those fields which are known to be safe to
>> merge ie. those, which can be parsed after merging. Also, if the top
>> most production in BNF specyfing field's value is #(values) it does
>> NOT mean the field is safe for merging although this seems to be
>> implied by the statement in the spec starting with "Multiple header
>> fields with the same field name MUST NOT be sent (...)"
>
>
> If a spec uses the list production but then doesn't allow proper parsing
> then that spec is buggy (such as Set-Cookie).

It's good to know whether Set-Cookie is the only exception among
well-known headers existed before rfc2616?

(Any headers introduced after rfc2616 should follow the rule; no slack for them)

Zhong Yu