Subject: Re: [Technical Errata Reported] RFC7230 (5257)

From: "Pe, Erwin (US)" <[email-masked]>
Date: Thu, 08 Feb 2018 16:30:40 +0000

Thanks for the correction. But I worry that with your proposed BNF, it is possible to make a production that ends with OWS. The current BNF does not allow productions that end in OWS, and I believe that is so that there wouldn’t be redundant OWS when the list is a field-value in a 
 
    header-field = field-name “:” OWS field-value OWS 
 
rule. To address the issues you’ve brought up, I propose another correction:
 
    #element => [ ( ("," [ OWS element ]) / element ) *( OWS "," [ OWS element ] ) ]

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From: Richard Gibson <[email-masked]>
Date: Mon, 12 Feb 2018 10:54:38 -0500

LGTM, but maybe a little more clear if you swap the order of the first 
two alternatives.

On 02/08/2018 11:30 AM, Pe, Erwin (US) wrote:
> Thanks for the correction. But I worry that with your proposed BNF, it 
> is possible to make a production that ends with OWS. The current BNF 
> does not allow productions that end in OWS, and I believe that is so 
> that there wouldn’t be redundant OWS when the list is a field-value in a

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From: Julian Reschke <[email-masked]>
Date: Mon, 12 Feb 2018 17:28:00 +0100

On 2018-02-12 16:54, Richard Gibson wrote:
> ...

FWIW, I believe we need to actually *verify* the ABNF against known 
inputs and have test cases.

Can anybody recommend an open source parser generator that consumes IETF 
ABNF?

Best regards, Julian