@Nullable
  public static GrExpression findExpressionChild(final PsiElement element) {
    for (PsiElement cur = element.getFirstChild(); cur != null; cur = cur.getNextSibling()) {
      if (cur instanceof GrExpression) return (GrExpression)cur;
    }
    return null;
  }
@Nullable
  public static GrExpression findExpressionChild(final PsiElement element)