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What is wrong with my simple grammar ? [message #1064902]

Fri, 21 June 2013 14:59

Vincent De Bry

Messages: 55
Registered: May 2013

Member

Hi,

I'm trying to define a grammar able to support writing the following text:

--NECST HEADER Scripts
#NESCT START
#NECST MIDDLE [free_text1][free_text2]

    --NECST ONE Script
    --NECST TWO Script

#NECST EXIT

For that, I have define the following grammar:

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.common.Terminals hidden (NECST_PARAM)

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

Model:{Model}
	'--NECST HEADER Scripts'
	(commentNecst+=CommandNecst*)?
	scripts+=Script+;
	
CommandNecst:
	'#NECST' command=ENUM_COMMANDNECST param+=NECST_PARAM*;
enum ENUM_COMMANDNECST : START|MIDDLE|EXIT;

Script:
	'--NECST' script=ENUM_SCRIPT 'Script'
;
enum ENUM_SCRIPT : ONE|TWO|THREE;

terminal NECST_PARAM : '[' -> ']';

But, I am not able to type anything after the first line.
What is wrong ?

Thanks

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Re: What is wrong with my simple grammar ? [message #1064907 is a reply to message #1064902]

Fri, 21 June 2013 15:15

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

Hi,

the problem is the hidden statement it should include ws and others. besides ws in keywords is a bad idea

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.common.Terminals hidden (NECST_PARAM,WS, ML_COMMENT, SL_COMMENT)

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

Model:{Model}
	'--NECST' 'HEADER' 'Scripts'
	(commentNecst+=CommandNecst*)
	scripts+=Script+;
	
CommandNecst:
	'#NECST' command=ENUM_COMMANDNECST param+=NECST_PARAM*;
enum ENUM_COMMANDNECST : START|MIDDLE|EXIT;

Script:
	'--NECST' script=ENUM_SCRIPT 'Script'
;
enum ENUM_SCRIPT : ONE|TWO|THREE;

terminal NECST_PARAM : '[' -> ']';

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

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Re: What is wrong with my simple grammar ? [message #1064924 is a reply to message #1064907]

Fri, 21 June 2013 16:31

Vincent De Bry

Messages: 55
Registered: May 2013

Member

Great Christian, Thanks !

I am now able to write the beginning of my file, except the final "#NECST EXIT".
Can you give me a tip for this issue ?

Thanks

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Re: What is wrong with my simple grammar ? [message #1064939 is a reply to message #1064924]

Fri, 21 June 2013 17:57

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

your grammar says the file ends with scripts

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

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Re: What is wrong with my simple grammar ? [message #1064950 is a reply to message #1064939]

Fri, 21 June 2013 21:02

Vincent De Bry

Messages: 55
Registered: May 2013

Member

Ok, so I've tried the following:

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.common.Terminals hidden (NECST_PARAM,WS, ML_COMMENT, SL_COMMENT)

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

Model:{Model}
	'--NECST' 'HEADER' 'Scripts'
	commandNecst+=CommandNecst*
	script+=Script+
	e=Exit
;

CommandNecst:
	'#NECST' command=ENUM_COMMANDNECST param+=NECST_PARAM*;
enum ENUM_COMMANDNECST : START|MIDDLE;

Exit:
	'#NECST' 'EXIT'
;

Script:
	'--NECST' script=ENUM_SCRIPT 'Script'
;
enum ENUM_SCRIPT : ON|TWO|THREE;

terminal NECST_PARAM : '[' -> ']';

But after having typed some "Script", the content assist keeps proposing me other "Script" but no "Exit" rule;and I don't know how to do so.

Any Idea ?
Thanks

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Re: What is wrong with my simple grammar ? [message #1064958 is a reply to message #1064950]

Fri, 21 June 2013 22:07

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

Hi,

you have to define content assist for custom datatype rules yourself by implementing the corresponding method in the proposalprovider
alternatively you can change the datatype rule to a real parser rule e.g.

Exit:
{Exit} '#NECST' 'EXIT'
;

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

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