anchor.diff:  // Use of this source code is governed by a BSD-style license that can be
   // found in the LICENSE file.
   
  -// See http://www.google.com/design/spec/style/typography.html
   
   import 'package:flutter/painting.dart';
   
   import 'colors.dart';
   
  -// TODO(eseidel): Font weights are supposed to be language relative!
  -// TODO(jackson): Baseline should be language relative!
  +// TODO(eseidel): Font weights are supposed to be language relative.
  +// TODO(jackson): Baseline should be language relative.
   // These values are for English-like text.
   // TODO(ianh): There's no font-family specified here.
  +
  +/// Material design text theme.
  +///
  +/// Definitions for the various typographical styles found in material design
  +/// (e.g., headline, caption). Rather than creating a [TextTheme] directly,
  +/// you can obtain an instance as [Typography.black] or [Typography.white].
  +///
  +/// To obtain the current text theme, call [Theme.of] with the current
  +/// [BuildContext] and read the [ThemeData.textTheme] property.
  +///
  +/// See also:
  +///
  +///  * [Typography]
  +///  * [Theme]
  +///  * [ThemeData]
  +///  * <http://www.google.com/design/spec/style/typography.html>
   class TextTheme {
   
     const TextTheme._(this.display4, this.display3, this.display2, this.display1, this.headline, this.title, this.subhead, this.body2, this.body1, this.caption, this.button);
  
positive.code:       caption  = const TextStyle(inherit: false, fontSize:  12.0, fontWeight: FontWeight.w400, color: Colors.white70, textBaseline: TextBaseline.alphabetic),
        button   = const TextStyle(inherit: false, fontSize:  14.0, fontWeight: FontWeight.w500, color: Colors.white,   textBaseline: TextBaseline.alphabetic);
  
    final TextStyle display4;
    final TextStyle display3;
    final TextStyle display2;
    final TextStyle display1;
    final TextStyle headline;
    final TextStyle title;
    final TextStyle subhead;
    final TextStyle body2;
    final TextStyle body1;
    final TextStyle caption;
    final TextStyle button;
  
    static TextTheme lerp(TextTheme begin, TextTheme end, double t) {
      return new TextTheme._(
        TextStyle.lerp(begin.display4, end.display4, t),
  
negative.code:       TextStyle.lerp(begin.button, end.button, t)
      );
    }
  }
  
  /// The two material design text themes.
  ///
  /// [Typography.black] and [Typography.white] define the two text themes used in
  /// material design. The black text theme, which uses darkly colored glyphs, is
  /// used on lightly colored backgrounds in light themes. The white text theme,
  /// which uses lightly colored glyphs, is used on darkly colored backgrounds in
  /// in light themes and in dark themes.
  ///
  /// To obtain the current text theme, call [Theme.of] with the current
  /// [BuildContext] and read the [ThemeData.textTheme] property.
  ///
  /// See also:
  ///
  ///  * [Theme]
  ///  * [ThemeData]
  ///  * <http://www.google.com/design/spec/style/typography.html>
  class Typography {
    Typography._();
  
    /// A material design text theme with darkly colored glyphs.
    static const TextTheme black = const TextTheme._black();
  
    /// A material design text theme with lightly colored glyphs.
    static const TextTheme white = const TextTheme._white();
  }
  