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JSON Grammar [message #1555333]

Fri, 09 January 2015 19:12

Luis De Bello

Messages: 95
Registered: January 2015

Member

Hi guys,

I am trying to create a simple json grammar but I am having some issues with the CA when the json is empty.

Grammar:

Document:
elements+=Object+;

Object:
"{" (elements+=KeyValuePair)? ("," elements+=KeyValuePair)* "}";

KeyValuePair:
key=STRING ":" value=STRING;

---------------------------------------------
Input in the editor:

{

}

In this scenario the CA suggests me two options "," and "}", I would like to know if there is any mistake in my grammar or how I can avoid this situation;I can modify the CA logic to handle this case in a different way but I am sure that there must be a good way of writing this grammar to avoid this side effect.

Thanks in advance

Luis

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Re: JSON Grammar [message #1555353 is a reply to message #1555333]

Fri, 09 January 2015 19:29

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

hi, i actually cannot reproduce that.
which xtext version to you use?

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

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Re: JSON Grammar [message #1555360 is a reply to message #1555353]

Fri, 09 January 2015 19:34

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

btw the comma is correct,

maybe you actually want to do the following


Object:
{Object}"{" (elements+=KeyValuePair ("," elements+=KeyValuePair)*)? "}";

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

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Re: JSON Grammar [message #1555538 is a reply to message #1555360]

Fri, 09 January 2015 21:54

Luis De Bello

Messages: 95
Registered: January 2015

Member

Hi Christian,

Thanks for the answer, I am using Xtext the latest version.

You grammar is better because I can have empty objects and the comma is suggested after having one element Smile