Eclipse Community Forums: TMF (Xtext) » Trouble with parser rules without assignments [SOLVED]

Home

Home » Modeling » TMF (Xtext) » Trouble with parser rules without assignments [SOLVED](Noob, pilot error)

Trouble with parser rules without assignments [SOLVED] [message #1180595]

Sun, 10 November 2013 22:37

Eclipse User

These ones work OK:

// zero argument instructions
Clr returns Clr:  {Clr} "clr" ;
Not returns Not: {Not} 'not';
Absa returns Absa: {Absa} 'absa';

However, these do not:

IsElse:  '@else' {IsElse};
IsEndif: '@endif' {IsEndif};

I don't notice any difference between that and this:

IsElse: {IsElse} '@else' ;
IsEndif: {IsEndif} '@endif' ;

And I don't have any explicit return types in my failing rules, but the same thing happened when I did try those.

IsElse and IsEndif are not showing up in my Ecore model and as a result they are not available anywhere else either.

I have to say that understanding parser rules is about the most difficult thing about Xtext!

[Updated on: Mon, 11 November 2013 09:40] by Moderator

Re: Trouble with parser rules without assignments [message #1180621 is a reply to message #1180595]

Sun, 10 November 2013 23:02

Eclipse User

Here's the abstract rule "Macro" which contains the 2 rules listed above, and one rule with one assignment that works OK:

Macro:
	IsPinConnected | IsElse | IsEndif 
;

Re: Trouble with parser rules without assignments [message #1180837 is a reply to message #1180621]

Mon, 11 November 2013 02:29

Eclipse User

IsElse: {IsElse} '@else' ;
IsEndif: {IsEndif} '@endif' ;

works fine for me.

Re: Trouble with parser rules without assignments [message #1181336 is a reply to message #1180837]

Mon, 11 November 2013 09:39

Eclipse User

Hi Christian,

Thanks for your help once again. The problem I was having had nothing to do with the grammar (big suprise)! I had messed up some paths in my project and the generated files from Xtext were landing outside of my workspace. Cleared that up and it is looking OK now!

The big clue (other than your remarks) were some errors in some of the generated files. I looked in there and found some parser rules that I had tried (and then deleted) yesterday. So I knew that the generated output in my workspace wasn't getting updated properly. I also checked the dates of the various files and found that the generated files in the workspace hadn't been updated since some time yesterday.

GW

Previous Topic:	Cross Reference within Quotation Marks
Next Topic:	Conflict between xtend and xtext language, model inferrer and dependencies?

Goto Forum:

-=] Back to Top [=-

Current Time: Sun Jul 20 20:58:16 EDT 2025

.:: Contact :: Home ::.

Breadcrumbs

Sign up to our Newsletter