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Unordered group problem [message #695243]

Mon, 11 July 2011 11:14

Dyson Mising name

Messages: 5
Registered: June 2011
Location: UK

Junior Member

Hi

I have the following fragment in my grammar:

SeqConfig: op=ART_ID ((',' config_elements+=SeqConfigElement)* & (',' labref=LabRef)? ) 
                     (',' config_elements+=SeqConfigElement)* ;

The intent is that the DSL allows a single LabRef within a set of SeqConfigElement's

This input works (where NOP is a valid ART_ID and x=y is a valid SeqConfigElement:
NOP x=y, lab

But this does not

NOP x=y, lab, a=b

The error marker given in the generated editor is attached to the 'a' in a=b and appears to relate to a separate fragment of the grammar.

I have not yet tried to test my understanding of unordered groups and their interaction with other elements as I wanted to check with more experienced users where I might be going wrong.

Cheers and thanks for any help you can give,
- Dyson

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Re: Unordered group problem [message #695246 is a reply to message #695243]

Mon, 11 July 2011 11:20

Alexander Nittka

Messages: 1193
Registered: July 2009

Senior Member

Hi,

you don't need unordered groups for that. Something like

SeqConfig: op=ART_ID ((',' config_elements+=SeqConfigElement)* (',' labref=LabRef) )?
(',' config_elements+=SeqConfigElement)* ;

should work
Alex

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