prefer_for_elements_to_map_fromiterable
Use 'for' elements when building maps from iterables.
Description
#The analyzer produces this diagnostic when Map.fromIterable
is used to build a map that could be built using the for
element.
Example
#The following code produces this diagnostic because fromIterable
is being used to build a map that could be built using a for
element:
dart
void f(Iterable<String> data) {
Map<String, int>.fromIterable(
data,
key: (element) => element,
value: (element) => element.length,
);
}
Common fixes
#Use a for
element to build the map:
dart
void f(Iterable<String> data) {
<String, int>{
for (var element in data)
element: element.length
};
}
Unless stated otherwise, the documentation on this site reflects Dart 3.7.3. Page last updated on 2025-05-08. View source or report an issue.