anchor.diff:  /// bodyText1 and bodyText2.
   ///
   /// ![](https://storage.googleapis.com/spec-host-backup/mio-design%2Fassets%2F1W8kyGVruuG_O8psvyiOaCf1lLFIMzB-N%2Ftypesystem-typescale.png)
  -///
  -/// ## Migrating from the 2014 names
   ///
   /// The Material Design typography scheme was significantly changed in the
   /// current (2018) version of the specification
  
positive.code:   /// If you do decide to create your own text theme, consider using one of
    /// those predefined themes as a starting point for [copyWith] or [apply].
    const TextTheme({
      TextStyle? headline1,
      TextStyle? headline2,
      TextStyle? headline3,
      TextStyle? headline4,
      TextStyle? headline5,
      TextStyle? headline6,
      TextStyle? subtitle1,
      TextStyle? subtitle2,
      TextStyle? bodyText1,
      TextStyle? bodyText2,
      this.caption,
      this.button,
      this.overline,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is headline1. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? display4,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is headline2. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? display3,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is headline3. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? display2,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is headline4. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? display1,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is headline5. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? headline,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is headline6. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? title,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is subtitle1. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? subhead,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is subtitle2. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? subtitle,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is bodyText1. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? body2,
      @Deprecated(
        'This is the term used in the 2014 version of material design. The modern term is bodyText2. '
        'This feature was deprecated after v1.13.8.',
      )
      TextStyle? body1,
    }) : assert(
           (headline1 == null && headline2 == null && headline3 == null && headline4 == null && headline5 == null && headline6 == null &&
            subtitle1 == null && subtitle2 == null &&
            bodyText1 == null && bodyText2 == null) ||
           (display4 == null && display3 == null && display2 == null && display1 == null && headline == null && title == null &&
            subhead == null && subtitle == null &&
            body2 == null && body1 == null),
           'Cannot mix 2014 and 2018 terms in call to TextTheme() constructor.',
         ),
         headline1 = headline1 ?? display4,
         headline2 = headline2 ?? display3,
         headline3 = headline3 ?? display2,
         headline4 = headline4 ?? display1,
         headline5 = headline5 ?? headline,
         headline6 = headline6 ?? title,
         subtitle1 = subtitle1 ?? subhead,
         subtitle2 = subtitle2 ?? subtitle,
         bodyText1 = bodyText1 ?? body2,
         bodyText2 = bodyText2 ?? body1;
  
    /// Extremely large text.
    final TextStyle? headline1;
  
negative.code: /// ...where "light" is `FontWeight.w300`, "regular" is `FontWeight.w400` and
  /// "medium" is `FontWeight.w500`.
  ///
  /// By default, text styles are initialized to match the 2018 Material Design
  /// specification as listed above. To provide backwards compatibility, the 2104
  /// specification is also available.
  ///
  /// To explicitly configure a [Theme] for the 2018 sizes, weights, and letter
  /// spacings, you can initialize its [ThemeData.typography] value using
  /// [Typography.material2018]. The [Typography] constructor defaults to this
  /// configuration. To configure a [Theme] for the 2014 sizes, weights, and letter
  /// spacings, initialize its [ThemeData.typography] value using
  /// [Typography.material2014].
  ///
  /// See also:
  ///
  