grammar org.xtext.example.commentws.CommentWs
hidden(ML_COMMENT)
...

CwFile:
	{CwFile}
	elems+=Elem*;

Elem:
	'begin' SEPARATOR content=ID SEPARATOR 'end' SEPARATOR;

SEPARATOR:
	LINE_RETURN;

ID:
	ALPHABETIC+ (WS+ ALPHABETIC+)*;

terminal ML_COMMENT:
	'/*'->'*/';

terminal ALPHABETIC:
	'a'..'z' | 'A'..'Z';

terminal WS:
	' ' | '\t';

terminal LINE_RETURN:
	'\r'? '\n';

begin
so/* a comment that should be ignored */me text
end