code: protected void formatCommaSeparatedList(Collection<? extends EObject> elements, IFormattableDocument document) {
  		for (final EObject element : elements) {
  			document.format(element);
  			final ISemanticRegionFinder immediatelyFollowing = this.textRegionExtensions.immediatelyFollowing(element);
  			final ISemanticRegion keyword = immediatelyFollowing.keyword(this.keywords.getCommaKeyword());
  			document.prepend(keyword, NO_SPACE);
  			document.append(keyword, ONE_SPACE);
  		}
  	}
docs: Format a list of comma separated elements.
  
  <p>This function does not considerer opening and closing delimiters, as
  {@link #formatCommaSeparatedList(Collection, ISemanticRegion, ISemanticRegion, IFormattableDocument)}.
  
  @param elements the elements to format.
  @param document the document.