bool test(E element)
) Removes all objects from this list that fail to satisfy test
.
An object o
satisfies test
if test(o)
is true.
List<String> numbers = ['one', 'two', 'three', 'four'];
numbers.retainWhere((item) => item.length == 3);
numbers.join(', '); // 'one, two'
Throws an UnsupportedError if this is a fixed-length list.
Source
/**
* Removes all objects from this list that fail to satisfy [test].
*
* An object [:o:] satisfies [test] if [:test(o):] is true.
*
* List<String> numbers = ['one', 'two', 'three', 'four'];
* numbers.retainWhere((item) => item.length == 3);
* numbers.join(', '); // 'one, two'
*
* Throws an [UnsupportedError] if this is a fixed-length list.
*/
void retainWhere(bool test(E element));