Adapts source
to be a Map<K2, V2>
.
Any time the set would produce a key or value that is not a K2
or V2
, the access will throw.
Any time K2
key or V2
value is attempted added into the adapted map, the store will throw unless the key is also an instance of K
and the value is also an instance of V
.
If all accessed entries of source
are have K2
keys and V2
values and if all entries added to the returned map have K
keys and V
] values, then the returned map can be used as a Map<K2, V2>
.
static Map<K2, V2> castFrom<K, V, K2, V2>(Map<K, V> source) => new CastMap<K, V, K2, V2>(source);
© 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dartlang.org/stable/2.0.0/dart-core/Map/castFrom.html