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Lists and Attributes without order [message #881345]

Mon, 04 June 2012 07:30

Eclipse User

Can anyone help me with the following grammar. We need to be able to allow
lists and unique values (attributes) mixed up, without any order, so I defined
the following grammar. (It is just an example, but I need it in a very similar case)

Town:
'TOWN' name=STRING
'START'
(size = Size) &
(elevation = Elevation)? &
(inhabitant += (Adult | Child)+
'END'
;

Size:
'SIZE' size=INT;

Elevation:
'ELEVATION' elevation=INT 'm';

Adult:
'ADULT' name=STRING;

Child:
'CHILD' name=STRING;

Actually this definition, doesn't allow the following syntax. The CHILD Ana Belen wouldn't be allowed, as ELEVATION is coming after ADULT.

TOWN "Madrid"
START
SIZE 3265038
ADULT "Mariano Rajoy"
ELEVATION 667m
CHILD "Ana Belen"
END

Anyone can knows, how I could improve the grammar.

I would need some grammar definition like this, but actually it is not supported.

Town:
'TOWN' name=STRING
'START'
description=(Size | Evelation? | Adult* | Child*)
'END'
;

Is there a workaround? Thanks a lot in advance.

[Updated on: Mon, 04 June 2012 08:01] by Moderator

Re: Lists and Attributes without order [message #881369 is a reply to message #881345]

Mon, 04 June 2012 08:23

Eclipse User

Hi!

AFAIK, lists have to be in one chunk. Maybe you can have

Town:
'TOWN' name=STRING
'START'
description+=(Size | Elevation | Adult | Child)*
'END'
;

and do some validation afterwards (one Size only, max one Elevation). Your model can filter the description list to deliver the inhabitants.

regards,
Vlad

Re: Lists and Attributes without order [message #881549 is a reply to message #881369]

Mon, 04 June 2012 16:17

Eclipse User

Vlad, thanks a lot for your help. Tomorrow I will discuss this with our colleagues, probably we will do as you recommend. Again, many thanks!

[Updated on: Mon, 04 June 2012 16:17] by Moderator

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