Implementation Report for RFC 2234 

ABNF implementation and interop report

Since it was published RFC 2234 has been referenced by at least 116
different RFCs:

    3502 3501 3470 3460 3459 3458 3455 3441 3435 3431
    3421 3420 3403 3391 3383 3368 3348 3340 3339 3325
    3300 3297 3282 3266 3261 3259 3192 3191 3179 3164
    3112 3108 3092 3091 3085 3084 3082 3801 3066 3028
    3018 3015 3000 2985 2967 2958 2957 2938 2926 2919
    2915 2913 2912 2910 2900 2885 2852 2849 2848 2846
    2832 2829 2822 2821 2813 2812 2808 2806 2800 2738
    2705 2700 2673 2653 2648 2646 2645 2640 2626 2614
    2609 2608 2600 2585 2583 2569 2565 2557 2554 2550
    2533 2530 2525 2506 2500 2486 2476 2449 2445 2426
    2425 2400 2389 2384 2384 2373 2345 2342 2327 2326
    2304 2303 2300 2299 2245 2244
   
Or to put it another way, around 9% of the RFCs published since
RFC 2234 have seen fit to reference it!

A list of the basic features provided by ABNF appears below. Associated
with each feature is a list of RFCs that use the feature. This list is not
meant to be exhaustive; it merely seeks to demonstrate that each
grammatical feature of ABNF has been used in multiple specifications.


Terminal values (%dD, %bB, %xH)

    2254 (%x) 2426 (%x) 2565 (%x) 2595 (%x) 2646 (%x)
    2822 (%d) 2957 (%d) 3018 (%b) 3179 (%x)

Concatenated terminal values (%dD.D, %bB.B, %xH.H)

    2565 (%x) 3161 (%x)

Alternatives (/)

    2426 2254 2565 2595 2646 2821 2822 2957 3066 3179

Incremental alternatives (=/)

    2426 2846 2595 3179

Value range alternatives (%dD-D, %bB-B, %xH-H)

    2254 (%x) 2426 (%x) 2565 (%x) 2595 (%x) 2646 (%x)
    2821 (%d) 2822 (%d) 2957 (%d) 2846 (%x) 3179 (%x)

Sequence group (())

    2254 2426 2565 2821 2822 2846 2957 3066 3179

Repetition (*element)

    2426 2565 2646 2821 2822 2957 3066

Variable repetition (<a>*<b>element)

    2426 2595 2646 2821 2822 2846 2957 3066 3179

Specific repetition (<n>element)

    2254 2821 2822

Optional ([element])

    2254 2426 2595 2646 2821 2822 2846

At least two ABNF validators have been written and are available at the
www.apps.ietf.org and www.ops.ietf.org web sites:

    http://www.apps.ietf.org/abnf.html
    http://www.ops.ietf.org/abnf/

A link to the source code for each of the validators is also provided on
the respective pages.