Home » Modeling » TMF (Xtext) » content assist/cross reference/scoping(I want content assist to limit cross referencing via scoping.)
| content assist/cross reference/scoping [message #555729] |
Fri, 27 August 2010 22:53  |
 Dennis 
Messages: 19
Registered: August 2010 |
Junior Member |
|
|
I have created two domain specific languages: MyWorld.xtext and MyVacations.xtext
Based on MyWorld grammar, I created a file called Europe.MyWorld (see below).
Europe {
Germany
England
}
Likewise, I created two more files: NorthAmerica.MyWorld and Asia.MyWorld.
NorthAmerica {
USA
Canada
}
Asia {
Japan
China
}
Furthermore, grammar MyVacations cross references to grammar MyWorld.
In MyVacations.xtext:
import "platform:/resource/org.xtext.myworld/src-gen/org/xtext/myworld/MyWorld.ecore" as myworld
import "http://www.eclipse.org/emf/2002/Ecore" as ecore
....
MyVacation hidden():element=[myworld::location]'.'attribute=[myworld::country];
....
Content assist will automatically cross reference ALL three files (Europe.MyWorld, NorthAmerica.MyWorld, Asia.MyWorld).
So far so good. For example, content assist will prompt <x> for Europe, NorthAmerica and Asia. And <y> for ALL the countries.
My summer vacation will be in <x>. The country will be in <y>.
Here's my question:
If my summer vacation is in Europe, can content assist prompt Germany and England which belongs to Europe and not the other countries?
In other words, I want to cross reference to Europe but to exclude North America and Asia.
Or to cross reference to Europe and Asia but to exclude North America.
My goal is not to have content assist to cross reference ALL the MyWorld files and to prompt ALL the available countries.
Is it possible to have content assist to limit cross referencing via scoping? I hope I make my question clear. Any help would be greatly appreciated.
|
|
|
| Re: content assist/cross reference/scoping [message #555752 is a reply to message #555729] |
Sat, 28 August 2010 08:54  |
|
Hi,
basically this is what scoping is for.
to make only the countries within the chosen continent visible is very easy:
with grammars like:
grammar org.xtext.example.myworld.MyWorld with org.eclipse.xtext.common.Terminals
generate myWorld "http://www.xtext.org/example/myworld/MyWorld"
World:
continents+=Continent*
;
Continent:
name=ID "{"
countries+=Country*
"}"
;
Country:
name=ID
;
grammar org.xtext.example.myvacation.MyVacation with org.eclipse.xtext.common.Terminals
generate myVacation "http://www.xtext.org/example/myvacation/MyVacation"
import "platform:/resource/org.xtext.example.myworld/src-gen/org/xtext/example/myworld/MyWorld.ecore" as myworld
Model:
vacations+=Vacation*;
Vacation:
"My" "summer" "vacation" "will" "be" "in" continent=[myworld::Continent] "." "The" "country" "will" "be" "in" country=[myworld::Country] "."
;
it's just this threeliner:
public class MyVacationScopeProvider extends AbstractDeclarativeScopeProvider {
public IScope scope_Vacation_country(Vacation vacation, EReference ref) {
return Scopes.scopeFor(vacation.getContinent().getCountries());
}
}
to do the same for
| Quote: |
Or to cross reference to Europe and Asia but to exclude North America.
|
which is also possible by scoping you have to be a bit more precise on what crieria you to want to do the restriction.
~Christian
Twitter : @chrdietrich
Blog : https://www.dietrich-it.de
|
|
| | |
| Re: content assist/cross reference/scoping [message #556102 is a reply to message #556074] |
Mon, 30 August 2010 19:08 |
Dennis
Messages: 19
Registered: August 2010 |
Junior Member |
|
|
Hi,
Unfortunately, the list of proposals is not based on formulas but it will need to be dynamically built.
What I mean is to predefine a subset of continents ahead of time dynamically.
For example, I want to vacation in Europe or Asia but I have not made up my mind yet . To do that, I can specify a subset of continents ahead of time. At this time, I have not decided exactly what continents but I know it will be either in Europe or Asia, and not South America, North America, or somewhere else.
I can only know what continent when I type "My summer vacation will be in .... (see below)
[Proposed Continents: Europe, Asia]
My summer vacation will be in Asia. The country will be in Japan.
Once Asia is typed in, content assist will only prompt Japan or China.
As you recall, going back to my original SELECT SQL grammer, I want to implement scoping for JOIN tables inside a query.
I have successfully implemented column scoping. When I type in a table name, content assist will prompt me for its column names.
If I have thousand of table names, I don't want content assist to prompt me for thousands of table names.
Because of my limited knowledge of xtext and Java programming experience, it is not likely that I am able to have content assist to prompt me for table1, table2
and table3 inside a query (see example below).
Namespace Blah{
Query TestBlah{
[RETURN: table1.column1]
FROM table1
INNER JOIN table2 ON table1.t1 = table2.t2
LEFT OUTER JOIN table3 ON table1.t1 = table3.t3
}
}
What I can possibly do is to try to explicity list all the tables that I would want to use in a query ahead of time.
Like:
[Posposed Tables: table1, table2, table3 ]
If I can change my grammar (RETURN, FROM, INNER JOIN, LEFT OUTER JOIN) to select tables from [Proposed Tables], content assist will now
be able to prompt me for only three tables: table1, table2 and table3.
I hope you finally understand what I want to accomplish.
|
|
|
| Re: content assist/cross reference/scoping [message #556110 is a reply to message #556102] |
Mon, 30 August 2010 19:57 |
|
Hi,
if you do it explicitly its all the same as it is for countries
grammar org.xtext.example.myvacation.MyVacation with org.eclipse.xtext.common.Terminals
generate myVacation "http://www.xtext.org/example/myvacation/MyVacation"
import "platform:/resource/org.xtext.example.myworld/src-gen/org/xtext/example/myworld/MyWorld.ecore" as myworld
Model:
vacations+=Vacation*;
Vacation:
"[" proposal=VacationProposal "]"
"My" "summer" "vacation" "will" "be" "in" continent=[myworld::Continent] "." "The" "country" "will" "be" "in" country=[myworld::Country] "."
;
VacationProposal:
"Proposed" "Continents" ":" poposedContentents+=[myworld::Continent] ("," poposedContentents+=[myworld::Continent])*
;
public IScope scope_Vacation_continent(Vacation vacation, EReference ref) {
return Scopes.scopeFor(vacation.getProposal().getPoposedContentents());
}
and with
[ Proposed Continents : Europe, Asia]
My summer vacation will be in
you will only get Europe and Asia as continent.
so do you want to do it explicitly or implcitly and if implicitly on which criteria,
~Christian
Twitter : @chrdietrich
Blog : https://www.dietrich-it.de
[Updated on: Mon, 30 August 2010 20:00] Report message to a moderator |
|
|
| Re: content assist/cross reference/scoping [message #556113 is a reply to message #556110] |
Mon, 30 August 2010 20:26 |
|
Here is a sample for an implicit / code based filtering
public class MyVacationScopeProvider extends AbstractDeclarativeScopeProvider {
public IScope scope_Vacation_country(Vacation vacation, EReference ref) {
return Scopes.scopeFor(vacation.getContinent().getCountries());
}
public IScope scope_Vacation_continent(Vacation vacation, EReference ref) {
IScope all = delegateGetScope(vacation, ref);
return new SimpleScope(Iterables.filter(all.getAllContents(), new Predicate<IEObjectDescription>() {
@Override
public boolean apply(IEObjectDescription input) {
if ("Asia".equals(input.getName()) || "Europe".equals(input.getName())) {
return true;
}
return false;
}
}));
}
}
~Christian
Twitter : @chrdietrich
Blog : https://www.dietrich-it.de
|
|
|
| Re: content assist/cross reference/scoping [message #556116 is a reply to message #556110] |
Mon, 30 August 2010 20:55 |
Dennis
Messages: 19
Registered: August 2010 |
Junior Member |
|
|
Hi,
You have demonstrated to me how to do it explicitly in your code. Thanks so much.
Both you and Alex are great help!
Of course, I want to do it implicitly.
If you go back to my SQL example posted above, the criteria is the table names from the JOINS.
By JOINS, I mean table1 from "FROM", table2 from "INNER" JOIN" and table3 from "LEFT" "OUTER" "JOIN".
If I have another table join, "LEFT" "OUTER" "JOIN" table4, table4 should be dynamically included in the scoping.
If there is no solution, my workaround is to hardcode the possible table names ahead of time.
Like:
[Posposed Tables: table1, table2, table3, table4 ]
If there is a way to do it dynamically, it would be wonderful!
|
|
|
| Re: content assist/cross reference/scoping [message #556118 is a reply to message #556116] |
Mon, 30 August 2010 20:59 |
|
Hi,
if you want to put all tables that are involved in the join on the scope this is explicit and works the same as for the columns/countries.
So just extract all tables from the joins, put them on a list, and create the scope from it,
Just think of
[Posposed Tables: table1, table2, table3, table4 ]
as
table1 JOIN table2 JOIN table3 JOIN table4
it might a bit more complicated depending on your metamodel and maybe (linkling) order but this should not be unsolveable.
~Christian
Twitter : @chrdietrich
Blog : https://www.dietrich-it.de
[Updated on: Mon, 30 August 2010 21:06] Report message to a moderator |
|
|
Goto Forum:
Current Time: Tue Apr 23 12:05:11 GMT 2024
Powered by FUDForum. Page generated in 0.03840 seconds |
] 
Search
Help
Register
Login
Home
