contains method
Whether the collection contains an element equal to element
.
This operation will check each element in order for being equal to element
,
unless it has a more efficient way to find an element equal to element
.
The equality used to determine whether element
is equal to an element of the iterable defaults to the Object.== of the element.
Some types of iterable may have a different equality used for its elements. For example, a Set may have a custom equality (see Set.identity) that its contains uses. Likewise the Iterable returned by a Map.keys call should use the same equality that the Map uses for keys.
Implementation
bool contains(Object? element) {
if (this == null) {
return false;
}
return this!.contains(element);
}