Re: unordered stuff in the parser combinator

David Pollak-4 wrote:
> 
> Howdy,
> 
> I'm working on a grammar using the parser combinator.
> 
> One of the challenges that I have is parsing stuff that must be present,
> but
> doesn't have to be in a particular order.  If I have 'dog', 'cat', 'fish'
> and 'moose' and my zoo is:
> 
> zoo = (dog ~ cat ~ fish ~ moose) | (dog ~ fish ~ cat ~ moose) | (dog ~
> fish
> ~ moose ~ cat) ...
> 
> Is there a better way to express this?
> 
> Thanks,
> 
> David
> 
> -- 
> lift, the secure, simple, powerful web framework http://liftweb.net
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> 
> 

Don't have time to knock up a proper solution right now, but here's a quick
pointer.  You'll need to define a method that takes a set of (remaining)
choices and returns a parser for those choices.  The method will call itself
recursively with the '>>' operator.

Hope that is enough to get you going!

Regards,

Andrew

Hope this is enough to get you going

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