atLeast method

bool atLeast(T value, { int sorter(T element, T value)?, })

Returns true if all elements in the iterable are equal to or greater than value.

Iterates over the entire iterable and uses a sorting function to compare value to each element in the iterable. If any element is less than value, this method returns false. Otherwise, if every element is greater than or equal to value, this method returns true.

If sorter is omitted, the method checks EqualityComparer.forType to see if a default sorting function exists. If one is found, it is used. If one is not found, this method throws an ArgumentError.

If the iterable is empty, a StateError will be thrown.

Implementation

bool atLeast(
  T value, {
  int Function(T element, T value)? sorter,
}) {
  final sorterImpl = sorter ?? EqualityComparer.tryForType<T>()?.sort;
  if (sorterImpl == null) {
    throw ArgumentError.notNull('sorter');
  }

  final iterator = this.iterator;
  if (!iterator.moveNext()) {
    throw StateError('Cannot call "atLeast" on an empty iterable.');
  }

  do {
    if (sorterImpl(iterator.current, value) < 0) {
      return false;
    }
  } while (iterator.moveNext());

  return true;
}