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lexer of Xtext (antlr) [message #725856]

Fri, 16 September 2011 01:26

alex.ren2006 is currently offline

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Messages: 46
Registered: June 2011

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Hi all,

The document says that we can negate a token like !'a'. In this way we specify a character which is not a. My question is how to specify a character which is neither a nor b. I tried !'ab'. It doesn't work. Any suggestion is highly appreciated.

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Re: lexer of Xtext (antlr) [message #725890 is a reply to message #725856]

Fri, 16 September 2011 05:54

Christian Dietrich is currently offline

Christian Dietrich

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Hi,

have a look at the org.eclipse.xtext.common.Terminals grammar: !('\n'|'\r')

~Christian

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

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Re: lexer of Xtext (antlr) [message #725891 is a reply to message #725856]

Fri, 16 September 2011 05:58

Alexander Nittka is currently offline

Alexander Nittka

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Hi,

the default terminal grammar should contain an example for that. Something like !('a'|'b') should work.

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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