目录

prefer_for_elements_to_map_fromIterable

Prefer for elements when building maps from iterables.

此规则自 Dart 2.3 版本起可用。

_规则集:recommended , flutter _

此规则提供 快速修复

详情

#

When building maps from iterables, it is preferable to use for elements.

Using 'for' elements brings several benefits including:

  • Performance
  • Flexibility
  • Readability
  • Improved type inference
  • Improved interaction with null safety

BAD:

dart
Map<String, WidgetBuilder>.fromIterable(
  kAllGalleryDemos,
  key: (demo) => '${demo.routeName}',
  value: (demo) => demo.buildRoute,
);

GOOD:

dart
return {
  for (var demo in kAllGalleryDemos)
    '${demo.routeName}': demo.buildRoute,
};

GOOD:

dart
// Map<int, Student> is not required, type is inferred automatically.
final pizzaRecipients = {
  ...studentLeaders,
  for (var student in classG)
    if (student.isPassing) student.id: student,
};

使用方法

#

要启用 prefer_for_elements_to_map_fromIterable 规则,请在你的 analysis_options.yaml 文件中,在 linter > rules 下添加 prefer_for_elements_to_map_fromIterable

analysis_options.yaml
yaml
linter:
  rules:
    - prefer_for_elements_to_map_fromIterable