Software Installation
• You‘ll find a CD with the required software on your desk
• Unzip the Eclipse distribution matching your OS
Windows users: Use a location close to the root directory
• Run the Eclipse executable
• Choose File -> Import -> Existing projects into workspace
• Select Archive file and choose workspace.zip from the CD

Workshop
Moritz Eysholdt, Sebastian Zarnekow, Jan Köhnlein

Moritz Eysholdt Jan Köhnlein
Sebastian Zarnekow

Moritz Eysholdt Jan Köhnlein
Sebastian Zarnekow

Moritz Eysholdt Jan Köhnlein
Sebastian Zarnekow

What is a
Domain Specific
Language (DSL)?

A domain-specific language (DSL)
is a formal, processable language
targeting at a specific viewpoint or aspect
of a system.

A domain-specific language (DSL)
is a formal, processable language
targeting at a specific viewpoint or aspect
of a system.
Its semantics, flexibility and notation is designed
in order to support working with that viewpoint
as good as possible.

Why would I
want to use a
DSL?

GPL vs DSL

GPL vs DSL

GPL vs DSL

Abstraction

Why isn‘t
everybody using
DSLs?

Complicated Expensive

Isn‘t text a
little bit old-
fashioned?

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
public boolean internalIsSameStructure(EObject left, EObject right) {
++counter;
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
}
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
++counter;
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
}
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
++counter;
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
• Formal
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
• Individual tools
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
• Formal
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
• Individual tools
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
• Formal
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
• Well established tools
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
• Individual tools
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
• Hard to evolve
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
• Formal
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
• Well established tools
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
i.remove();
}
}
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
• Individual tools
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
• Hard to evolve
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
return false;
}
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
• Formal
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
• Well established tools
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
}
} • Easy to evolve
i.remove();
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
• Individual tools
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
• Hard to evolve
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
• Editing with mouse
}
return false;
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
• Formal
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
• Well established tools
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
}
} • Easy to evolve
i.remove();
return relevantChildren;
}
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

}
protected String getErrorMessage() {
return errorMessage.toString();
}
Graphics
public boolean isSameStructure(EObject left, EObject right) {
counter = 0;
return internalIsSameStructure(left, right);
}
• High-level views
public boolean internalIsSameStructure(EObject left, EObject right) {
•
++counter;
Suggests non-formalism
if (!isSameClass(left.eClass(), right.eClass())) {
errorMessage.append("Classes are not equal: " + left + " != " + ri
• Individual tools
return false;
}
List<EObject> leftChildren = getRelevantChildren(left);
• Hard to evolve
List<EObject> rightChildren = getRelevantChildren(right);
if(leftChildren.size() != rightChildren.size()) {
errorMessage.append("Number of children differs " + left + " " + r
• Editing with mouse
}
return false;
for (int i = 0; i < leftChildren.size(); ++i) {
if(!internalIsSameStructure(leftChildren.get(i), rightChildren.get
errorMessage.append("Children differ " + left + " " + right +
return false;
}
}
Text
return true;
}
protected boolean isSameClass(EClass left, EClass right) {
return left.getName().equals(right.getName())
}
• Detailed views
&& left.getEPackage().getNsURI().equals(right.getEPackage().g
• Formal
protected List<EObject> getRelevantChildren(EObject _this) {
List<EObject> relevantChildren = new ArrayList<EObject>(_this.eContents(
• Well established tools
for (Iterator<EObject> i = relevantChildren.iterator(); i.hasNext();) {
EObject next = i.next();
if (!isRelevantChild(_this, next)) {
} • Easy to evolve
i.remove();
•
}
} Editing with keyboard
return relevantChildren;
protected boolean isRelevantChild(EObject container, EObject child) {
return true;

Showtime !
• In your Eclipse workbench
• Choose Run->Run configurations...
• Double click on Eclipse Application
• Go to the Arguments tab and add
-XX:MaxPermSize=128m
to the VM arguments
• Click on Run

A Guided Example
entity Conference {
property Name : String
on
Attendees refs many Pers
Sp eakers refs many Speaker
}
entity Person {
property Name : String
}
{
enti ty Speaker extends Person
n
Sessions refs many Sessio
}
entity Session {
property Title: String
property IsTutorial : Bool
}

Grammar Language
grammar org.xtext.cg2009.Entities
with org.eclipse.xtext.common.Terminals
generate entities "http://www.xtext.org/cg2009/Entities"
Model :
(entities += Entity)+;
Entity returns Entity:
'entity' name=ID ('extends' superType=[Entity])? '{'
(properties+=Property)*
'}';
Property:
SimpleProperty | ReferenceProperty;
SimpleProperty:
'property' name=ID ':' type=('String'|'Number'|'Bool');
ReferenceProperty :
name=ID 'refs' ('one' | many?='many')? type=[Entity];

Edit SQL with Xtext
CREATE TABLE Conferences (
id INTEGER NOT NULL PRIMARY KEY,
• Only
)
name CHAR(50)
Create-Statements
• List of columns

Edit SQL with Xtext
CREATE TABLE Conferences (
id INTEGER NOT NULL PRIMARY KEY,
name CHAR(50)
• Enhance with
)
Foreign Keys CREATE TABLE Speaker (
name CHAR(50),
id INTEGER,
FOREIGN KEY (id)
REFERENCES Conference(id)
)

What’s wrong with it?

Cross References

Cross References
Model Element

Cross References
Element Name
Model Element

Cross References
Element Name
resolve
Model Element

Cross References
Element Name
resolve determin
Model Element

Problem:
Names may not be ambiguous.

Problem:
Names may not be ambiguous.
Solution:
Implement a ScopeProvider!

Problem:
Names may not be ambiguous.
Solution:
Implement a ScopeProvider!
A Scope is a context specific, hierarchical
collection of all reachable model elements
and their respective names.

Scope Provider
Make Foreign Keys work!
public IScope scope_ForeignKey_from(
ForeignKey context, EReference reference) {
Table fromTable = (Table) context.eContainer();
return createTableScope(fromTable);
}

Meta-Model Inference
grammar org.xtext.codeGeneration.Entities
with org.eclipse.xtext.common.Terminals
generate entities "http://www.xtext.org/CG2009/Entities"
Model :
(entities += Entity)+;
Entity returns Entity:
'entity' name=ID ('extends' superType=[Entity])? '{'
(properties+=Property)*
'}';
Property:
SimpleProperty | ReferenceProperty;
SimpleProperty:
'property' name=ID ':' type=('String'|'Number'|'Bool');
ReferenceProperty :
name=ID 'refs' ('one' | many?='many')? type=[Entity];

Model Conferences
with Xtext
How do I create a language
for an existing meta-model?

Model Conferences
with Xtext

Validate Your
Conference
1. Have a look at the generated Validator-Stub.
2. Implement some checks for your language.
3. Check out the results.
@Check
public void checkSpeakersName(Speaker speaker) {
assertTrue("Speaker's name is to short.",
ConferencesLanguagePackage.SPEAKER__NAME,
speaker.getName().length() >= 2);
}

Convention
over
Configuration

Configured with
Google Guice
class MyDslRuntimeModule extends DefaultRuntimeModule {
Class<? extends ServiceInterface> bindService() {
return MyServiceImplementation.class;
}
}

Extensible Language
Generator
• Generates a lot of Java code
• Composed of fragments
• Customizable
• Add your own
fragments!

http://www.wordle.net/

Formatting
Pretty Printing
Code Beautification
import
<Literature.entities> entity
City {Int id; String
name;}
entity Store { Int
id; String name;
Int
city
references
City.
id; }

Formatting
Pretty Printing
Code Beautification
import
<Literature.entities> entity
City {Int id; String
name;}
entity Store { Int
id; String name;
Int import <Literature.entities>
city
references entity City {
City. Int id;
id; } String name;
}
entity Store {
Int id;
String name;
Int city references
City.id;
}

Formatting
Pretty Printing
Code Beautification
import
<Literature.entities> entity
City {Int id; String
name;}
entity Store { Int
id; String name;
Int import <Literature.entities>
city
references entity City {
City. Int id;
id; } String name;
}
entity Store {
Int id;
String name;
Int city references
City.id;
}

Formatting
Pretty Printing Code Beautification
import
<Literature.entities> entity
City {Int id; String
name;}
entity Store { Int
id; String name;
Int import <Literature.entities>
city
references entity City {
City. Int id;
id; } String name;
}
entity Store {
Int id;
String name;
Int city references
City.id;
§ 1. At ... do ...
}
§ 2. At ... do ...
§ 3. At ... do ...
§ 4. At ... do ...
...

Integration with EMF

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>>
XMIResource
Resource

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>>
XMIResource
Resource

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>> XMI
XMIResource
Resource

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>> XMI
XMIResource
Resource

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>> XMI
XMIResource
Resource
XtextResource

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>> XMI
XMIResource
Resource
XtextResource

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>> XMI
XMIResource
Resource
XtextResource Text

Integration with EMF
eclipse
Any EMF-based modeling
Code Generator GMF Editor P R O J E C T
Component
<<abstract>> XMI
XMIResource
Resource
XtextResource Text
Parser Linker Serializer
ValueConverter ScopeProvider Formatter

EMF Index
• Indexes all resources in workspace
• Query elements and cross-references
• Efficient scoping

EMF Index
• Indexes all resources in workspace
• Query elements and cross-references
• Efficient scoping
Load
Resources

Learn more at
http://www.xtext.org