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mismatched input [message #689754]

Tue, 28 June 2011 09:41

Robin

Messages: 25
Registered: August 2010

Junior Member

Hi,

I am a bit stuck while designing a grammar. Hopefully, someone can help.

This is my grammar so far:

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.common.Terminals

generate myDsl "http://www.xtext.org/example/mydsl/MyDsl"

Model:
	{Model}
	(tokens+=Token)*;

Token:
	'<TOKEN var1="' var1=ID '" var2="' var2=ID '">';

And this is an instance of the language:

<TOKEN var1="value1" var2="value2">

But I get the error: mismatched input '<EOF>' expecting '">'.

Why? It seems to me it is just consuming the '">' ??! Confused

Regards, Robin

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Re: mismatched input [message #689769 is a reply to message #689754]

Tue, 28 June 2011 10:14

Alexander Nittka

Messages: 1193
Registered: July 2009

Senior Member

Hi,
your token rule does not look good. Why not use something like

Token:'<TOKEN' 'var1' '=' var1=STRING 'var2' '=' var2=STRING '>';

Whitespaces in tokens are not recommended and parsing within Strings ist not trivial.

Alex

Need training, onsite consulting or any other kind of help for Xtext?
Go visit http://xtext.itemis.com or send a mail to xtext@itemis.de

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Re: mismatched input [message #689797 is a reply to message #689754]

Tue, 28 June 2011 11:32

Robin

Messages: 25
Registered: August 2010

Junior Member

Ah, that works! Thank you so much! Smile

So I guess, the parser just consumes everything that is not declared to be taken care of??

Regards, Robin

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Re: mismatched input [message #689820 is a reply to message #689797]

Tue, 28 June 2011 12:37

Alexander Nittka

Messages: 1193
Registered: July 2009

Senior Member

Hi,

before the parser does anything, the lexer chops up the input into tokens according to the definitions of terminals (and keywords) defined in your grammar (and the ones you inherit from). It is well possible that already the lexer does not produce the tokens you were expecting.

Alex

Need training, onsite consulting or any other kind of help for Xtext?
Go visit http://xtext.itemis.com or send a mail to xtext@itemis.de

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