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cross-reference ambiguity with grammar rules [message #1696024]

Thu, 21 May 2015 09:06

Eleanor Richie

Messages: 125
Registered: August 2014

Senior Member

I currently have cross-reference defined in a place that will solve a lot of issues in the cross referencing but I have to OR with this cross reference another rule that causes ambiguity and adding a syntactic predicate for anyone of them totally disables the other.
Example:

leaf_name returns LeafName:

declarations=[Declarations] | otherName=ID | string=String

;

Declarations cross reference a lot of rules that has something like ('int' name=ID)
All I want from the parser/linker is to link/cross-reference the object IF and ONLY IF it found a declaration with this name otherwise it considers it as a normal ID with no cross-reference.
I tried adding syntactic predicates to anyone of them but It didnt solve my issue.
Any help will be appreciated Smile

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Re: cross-reference ambiguity with grammar rules [message #1696027 is a reply to message #1696024]

Thu, 21 May 2015 09:14

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

Hi,

since cross references are not a parsing thing but done afterwards, the grammar from a parser point of view looks like

declarations=ID | otherName=ID | string=String

=> on parsing side this cannot be resolved.

of course you could hook into linking and could create a fake Declarations on the fly,
but this is not what you want to do.

if this is not an existing language i strictly recommend you to differentiate both cases syntactically

another possiblility would be not to cross link at all and do the byname lookup in generation, hyperlinking etc manually

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

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Re: cross-reference ambiguity with grammar rules [message #1696029 is a reply to message #1696027]

Thu, 21 May 2015 09:19

Eleanor Richie

Messages: 125
Registered: August 2014

Senior Member

what is the byname lookup? will it do the same job as cross referencing in the grammar? I hope the byname lookup can get me out of grammar cross referencing.
Does hyperlinking help in adding a link between two objects and adding them in the index?
I actually added the cross-reference just for the sake of scoping (and later I found it enabled the go to declaration and quick fixes for free Very Happy

[Updated on: Thu, 21 May 2015 09:29]

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Re: cross-reference ambiguity with grammar rules [message #1696030 is a reply to message #1696029]

Thu, 21 May 2015 09:28

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

No,

then you would not have cross reference and you would have to care yourself.

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

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Re: cross-reference ambiguity with grammar rules [message #1696032 is a reply to message #1696030]

Thu, 21 May 2015 09:30

Eleanor Richie

Messages: 125
Registered: August 2014

Senior Member

how can I start in byname lookup and these stuff?

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Re: cross-reference ambiguity with grammar rules [message #1696033 is a reply to message #1696030]

Thu, 21 May 2015 09:30

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

of course you could try to dive deep into metamodel and linking and

- use a metamodelpostprocesstor to add the cross reference to the model
- make it transient though the transientvalueservice
- adopt linking with your logik.

but it cannot deeply help you with that and dont know if it will finally work out.

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

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