Re: [search-ws] Possible type in BNF?

[Ashley Sanders <a.sanders@manchester.ac.uk>]

Farrukh,

> The following (first) row in BNF does not quite seem right:
> 
> sortedQuery
> ::=
> prefixAssignment sortedQuery
> | scopedClause ['sortby' sortSpec]

The BNF in the document is correct. What is is allowing is
multiple prefixAssignments before the scopedClause.

A couple of years ago I wrote a CQL parser (using
Boost.Spirit which admittedly uses a different notation)
and it worked out okay. If anyone's interested, my
Boost.Spirit notation for the above is as follows:

    sortedQuery = *prefixAssignment >> scopedClause;

Which I think is perhaps a little clearer -- it is
saying that a sortedQuery is any number of prefixAssignments
followed by a scopedClause. (I never did get around to
implementing the sortby stuff.)

I hope that helps,

Ashley.
-- 
Ashley Sanders               a.sanders@manchester.ac.uk
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