+import org.simantics.graph.compiler.internal.ltk.ISource;
+import org.simantics.graph.compiler.internal.ltk.Location;
+import org.simantics.graph.compiler.internal.ltk.Problem;
+import org.simantics.graph.compiler.internal.ltk.SourcePart;
+import org.simantics.graph.compiler.internal.ltk.antlr.ANTLRUtils;