docs: public FieldType calcFieldType( String content ) {
          final SnippetBuilder.SnippetType snippetType = SnippetBuilder.getType( content );
          if ( snippetType.equals( SnippetBuilder.SnippetType.FORALL ) ) {
              return FieldType.FORALL_FIELD;
          } else if ( !snippetType.equals(
                  SnippetBuilder.SnippetType.SINGLE ) ) {
              return FieldType.NORMAL_FIELD;
          }
          for ( String op : operators ) {
              if ( content.endsWith( op ) ) {
                  return FieldType.OPERATOR_FIELD;
              }
          }
          return FieldType.SINGLE_FIELD;
      }