Contents

super_goes_last

Contents

Place the super call last in a constructor initialization list.

This rule has been removed as of the latest Dart releases.

Details

#

NOTE: This rule is removed in Dart 3.0.0; it is no longer functional.

DO place the super call last in a constructor initialization list.

Field initializers are evaluated in the order that they appear in the constructor initialization list. If you place a super() call in the middle of an initializer list, the superclass's initializers will be evaluated right then before evaluating the rest of the subclass's initializers.

What it doesn't mean is that the superclass's constructor body will be executed then. That always happens after all initializers are run regardless of where super appears. It's vanishingly rare that the order of initializers matters, so the placement of super in the list almost never matters either.

Getting in the habit of placing it last improves consistency, visually reinforces when the superclass's constructor body is run, and may help performance.

BAD:

dart
View(Style style, List children)
    : super(style),
      _children = children {

GOOD:

dart
View(Style style, List children)
    : _children = children,
      super(style) {

Usage

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To enable the super_goes_last rule, add super_goes_last under linter > rules in your analysis_options.yaml file:

analysis_options.yaml
yaml
linter:
  rules:
    - super_goes_last