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first property
String firstReturns the first element.
Throws a StateError if this is empty. Otherwise returns the first element in the iteration order, equivalent to this.elementAt(0).
Source
String get first => readClasses().first;
  © 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
 https://api.dartlang.org/stable/1.24.3/dart-svg/AttributeClassSet/first.html