gilbert@aimmi.UUCP (Gilbert Cockton) (10/13/86)
My research on dialogue specification has lead me towards the idea of
generating/encapsulating `big' structures from/within smaller ones.
Two level grammars seem to do the same (and much more, i.e. infinite
sets of productions can be specified in the meta-syntax) so I'd like
to bone-up (a little!) on 2LGs.
There are passing historical references in compiler books, and
there's a chapter by Koster in Bauer and Eickel's LNCS 21. However, I've
never been able to find a succinct summary of the 2LG arsenal. I don't want to
read any of van Wijngaarden's original work either. I just need to understand
the bare bones of 2LGs, I've no intention of wrestling with any unsolved
problems or open/esoteric research issues kept alive by Formal
Language and Automata types.
My interest is in the expression of consistency in context free
grammars and networks, something to which BNF and syntax diagrams aren't
well suited (see work by Phyllis Reisner, Tom Green and Steve Payne).
The use of of 2 levels to express context sensitive constraints
and anomalies doesn't interest me, as such things should be avoided in
Human-Computer interaction languages.
So, I'd be grateful for any suggestions on quick and concise
references. If there's enough material, I'll send a summary to the
net.
Thanks in advance
--
Gilbert Cockton, Scottish HCI Centre, Ben Line Building, Edinburgh, EH1 1TN
JANET: gilbert@uk.ac.hw.aimmi ARPA: gilbert%aimmi.hw.ac.uk@cs.ucl.ac.uk
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