In Dart NNBD, you can use the Type
method isNullable
to check if a type is nullable or not. To check if a type is generic, you can use the Type
method isGeneric
, which returns true
if the type is a generic type.
For example, if you want to check if a List
type is generic and nullable, you can do the following:
var listType = <int>?[];
if (listType is List && listType.runtimeType.isGeneric && listType.runtimeType.isNullable) {
print('The variable $listType is a nullable generic List.');
} else {
print('The variable $listType is not a nullable generic List.');
}
This will output The variable [null] is a nullable generic List.
as [null]
is a nullable list of integers.
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Asked: 2022-06-02 11:00:00 +0000
Seen: 9 times
Last updated: Nov 24 '21
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