Dart Primary Constructors & New Constructor Syntax Skill

Use this skill when helping users write, refactor, or debug code using Dart's Primary Constructors feature.

Dart Version Requirements

• Dart 3.13 and above: Primary constructors are enabled by default.
• Dart 3.12: The feature is available but experimental. Users must explicitly enable the experiment flag primary-constructors via --enable-experiment=primary-constructors or in analysis_options.yaml:

analyzer:
  enable-experiment:
    - primary-constructors

• Dart 3.11 and earlier: Primary constructors are not supported.

1. Overview

Primary Constructors allow developers to declare a non-redirecting generative constructor as well as a set of instance variables directly in the class header. This significantly reduces boilerplate and improves code readability.