Need reference to good ABNF for \uXXXX syntax

Doug Ewell doug at
Fri Apr 16 10:25:38 CDT 2021

Martin J. Dürst wrote:

> What bothers me in this grammar is that the first "\u" isn't anywhere
> in sight, but the second one is there. It would be much clearer if
> either the first "\u" is at the start of hexchar, i.e.

Sorry, I neglected to include this line, which precedes everything I did quote:

SESC = "\" ( %x22 / %x2F / %x5C / %x62 / %x66 / %x6E / %x72 / %x74 /
             (%x75 hexchar) )

SESC incorporates all the other backslash-escaped characters. It, not hexchar, is the real entity referenced by everything else.

Doug Ewell, CC, ALB | Lakewood, CO, US |

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