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Thu, 23 July 2015 19:18

Eclipse User

I have question related to the difference between Partial and full parse.

If i have file with more that 15000 line, and this file was parsed.
By changing two or three lines in it, does xtext will parse all the file again or partial parsing will be done, if the answer was that partial parsing will work, how could we get the difference between the two models, i mean the difference between the model before that change and after the change.
in other words, how could we get the nodes in datamodel of xtext which updated?

[Updated on: Thu, 23 July 2015 19:19] by Moderator

Thu, 30 July 2015 13:02

Eclipse User

Hi Kimi,

there is no API that allows to obtain the exact elements that will be
replaced by a partial parsing run.

Generally Xtext will try to minimize the region that needs to be
reparsed if you type in the editor. Often that's not possible due to
lookahead constraints e.g., but on average there is same potential to
safe a few CPU cycles. OTOH parsing is usually not a bottle-neck as long
as you don't use backtracking or large syntactic predicates.

Best,
Sebastian
--
Looking for professional support for Xtext, Xtend or Eclipse Modeling?
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Sat, 01 August 2015 00:51

Eclipse User

Hi sebastian
I have create testcase contains 5 lines, as shown below
Class x (
Int a ; //line2
Int b; // line 3
Int c; //line 4
)
As you can see "a", "b" and "c" represent leaf nodes in the model of xtext based on my grammer
The issue is that by renaming "int b" to "int bb" another complete model created, and my expectation was small modification in the model generated by xtext
What i mean is that my expectation was to keep the model as its and replace the node which represent "int b" with another node only, but i found another model with another objects created

Thu, 06 August 2015 03:58

Eclipse User

Another question, do we have a way to get notified with every change in xtext datamodel,

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