At 6:03 PM -0500 on 8/22/10, John McKown wrote about Re: LARL vs. alignment requirement/pseudo-XML notation:
Ah! Many thanks. I had heard of BNF, but don't really have it at the front of my head, like I do XML.
You run into all the time if you read Internet RFCs. BNF format is used to define what is called Symbolic Atoms. For example if you were using this notation to define the structure of an assembler DC instruction you would say that the parm is composed of an occurrence factor, a length, a type, and a parm-value. The type would list all the different types (Numeric) that use quotes as one type and another (Addresses) that use parens. The Address type would use BNF to define these (A |Q | S | etc) and for the data would define them as (H | F | D | etc).
