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single property
Number singleChecks that this iterable has only one element, and returns that element.
Throws a StateError if this is empty or has more than one element.
Source
Number get single {
  int len = this.length;
  if (len == 1) {
    return getItem(0);
  }
  if (len == 0) throw new StateError("No elements");
  throw new StateError("More than one element");
}
  © 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/NumberList/single.html