EN_raw_map_key_type_not_assignable

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                  Diagnosticschevron_right

                  map_key_type_not_assignable

            map_key_type_not_assignable

Details about the 'map_key_type_not_assignable' diagnostic produced by the Dart analyzer.

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The element type '{0}' can't be assigned to the map key type '{1}'.

              Description

              #

              The analyzer produces this diagnostic when a key of a key-value pair in a
              map literal has a type that isn't assignable to the key type of the map.

              Example

              #

              The following code produces this diagnostic because `2` is an `int`, but
              the keys of the map are required to be `String`s:

                dart

var m = <String, String>{2: 'a'};

                content_copy

              Common fixes

              #

              If the type of the map is correct, then change the key to have the correct
              type:

                dart

var m = <String, String>{'2': 'a'};

                content_copy

If the type of the key is correct, then change the key type of the map:

                dart

var m = <int, String>{2: 'a'};

                content_copy

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                Unless stated otherwise, the documentation on this site reflects Dart 3.13.3. Report an issue.