length property Null safety

int length
override

The number of objects in this list.

The valid indices for a list are 0 through length - 1.

Implementation

int get length => JS("int", "#.length", this);
void length= (int value)
override

Changes the length of this list.

If newLength is greater than the current length, entries are initialized to null. Increasing the length fails if the element type does not allow null.

Throws an UnsupportedError if the list is fixed-length or if attempting to enlarge the list when null is not a valid element.

Implementation

set length(int value) {
  throw new UnsupportedError("Cannot resize immutable List.");
}