@Inject ParseHelper<XExpression> parseHelper

var variable=parseHelper.parse('''123''')

 @InjectWith(CLangInjectorProvider)

	public T parse(InputStream in, URI uriToUse, Map<?, ?> options, ResourceSet resourceSet) {
		resourceHelper.setFileExtension(fileExtension);
		Resource resource = resourceHelper.resource(in, uriToUse, options, resourceSet);
		final T root = (T) (resource.getContents().isEmpty() ? null : resource.getContents().get(0));
		return root;
	}

resource.getContents().isEmpty()

def expandBlock(XBlockExpression block){
var variable=XbaseFactory.eINSTANCE.createXVariableDeclaration()
variable.name=name
var sl=XbaseFactory.eINSTANCE.createXStringLiteral
sl.value="123"
variable.right=sl;
block.expressions+=variable
block.expressions.move(0,variable)	
}

var variable=parser.parse('''var db=Service.getService(IDBService)''')
block.expressions+=variable
block.expressions.move(0,variable)	

public <ReturnType>doSomething(<Parameters>) {
// manual code here body='''....'''
someStatement();
someOtherStatement();
doSomethingInternal(params);
}
private <ReturnType>doSomethingInternal(<Parameters>) {
// generated code here body=model.expression
// ....
}