anchor.diff:  
     /// Can control the formatting of double columns, for example give column
     /// with name 'A' you can specify
  -  /// {'format': 'A': (double x) => x.toStringAsPrecision(5)}
  -  Map<String, dynamic> options = <String, dynamic>{
  +  /// {'format': 'A': (x) => (x as double).toStringAsPrecision(5)}
  +  static final Map<String, dynamic> defaultOptions = <String, dynamic>{
       'columnSeparation': ' ',
       'format': <String, String Function(dynamic)>{},
     };
  +
  +  Map<String, dynamic> _options;
   
     /// Construct an empty (0 rows) table with columns.
     Table({List<String> colnames, Map<String,dynamic> options}) {
  
positive.code:         _data.add(Column([], name));
        }
      }
      options ??= this.options;
      for (var key in options.keys) {
        this.options[key] = options[key];
      }
    }
  
  
negative.code:       }
      }
      for (var i = 0; i < nrow + 1; i++) {
        res.add(out[i].join(defaultOptions['columnSeparation']));
      }
      return res.join('\n');
    }
  