first property Null safety

E first
inherited

Returns the first element.

Throws a StateError if this is empty. Otherwise returns the first element in the iteration order, equivalent to this.elementAt(0).

Implementation

@override
E get first => _base.first;
void first=(E value)
override

The first element of the list.

The list must be non-empty when accessing its first element.

The first element of a list can be modified, unlike an Iterable. A list.first is equivalent to list[0], both for getting and setting the value.

final numbers = <int>[1, 2, 3];
print(numbers.first); // 1
numbers.first = 10;
print(numbers.first); // 10
numbers.clear();
numbers.first; // Throws.

Implementation

@override
set first(E value) {
  if (isEmpty) throw RangeError.index(0, this);
  this[0] = value;
}