Ah! Many thanks. I had heard of BNF, but don't really have it at the
front of my head, like I do XML.

On Sun, 2010-08-22 at 19:56 +0000, john gilmore wrote:

> John McKown wrote:
>
> <begin snippet>
> Neither is good "pseudo-xml", if that is what was intended
>
> <joke type="technical">
> ...
> </joke>
>
> is at least syntactically correct XML.
> </end snippet>
>
> I write XML and the like on occasion, but I was not writing either XML or 
> pseudo-XML on this occasion.  Backus used broken brackets, '<', and '>', as 
> delimiters in what came to be called BNF, as in
>
> <decimal digit> ::= 0|1|2|3|4|5|6|7|8|9    ^,
>
> in the 1960s, and I and others find it convenient in many definitional 
> contexts: it permits a brief descriptive phrase to be used as the manipulable 
> and largely self-explanatory name of an entity.
>
> None of this should be interpreted as an effort to delegitimate the use of 
> broken brackets in XML.  I can see no objection to that, but in a period of 
> radical historical amnesia it is perhaps worth noting that notation thought 
> by some to have been introduced with XML in fact has a long prior history.
>
> John Gilmore

Reply via email to