Capability topic

MacroCapability Documentation

MacroCapability defines what parts of a declaration should be collected and made available to a macro during code generation. By enabling only the information you need, you reduce analysis cost and improve runtime performance.

Each flag controls a specific capability, and some filters only apply when their parent capability is enabled.

For example:

  • filterClassInstanceFields applies only if classFields == true
  • filterMethods applies only if classMethods == true

Capabilities Overview (Table)

Capability Type Applies When Description
classFields bool — Collect all fields declared in the class.
filterClassInstanceFields bool classFields == true Include only instance fields.
filterClassStaticFields bool classFields == true Include only static fields.
filterClassIgnoreSetterOnly bool classFields == true Ignore “setter-only” virtual fields; include getters/setters/vars.
filterClassFieldMetadata String classFields == true Filter fields by metadata. Use "*" or comma-separated list.
classConstructors bool — Collect all constructors declared in the class.
filterClassConstructorParameterMetadata String classConstructors == true Filter constructor parameters by metadata. "*" allowed.
mergeClassFieldWithConstructorParameter bool classConstructors == true Merge field metadata with constructor parameter metadata.
inspectFieldInitializer bool classConstructors == true Detect inferred field initializers from parent/super types. (Expensive)
classMethods bool — Collect all methods declared in the class.
filterClassInstanceMethod bool classMethods == true Include only instance methods.
filterClassStaticMethod bool classMethods == true Include only static methods.
filterMethods String classMethods == true Filter included methods ("*" or list: build,toJson)
filterClassMethodMetadata String classMethods == true Filter methods by metadata. "*" allowed.
topLevelFunctions bool — Collect all function declared in the library.
collectClassSubTypes bool — Collect all subclasses of this class (for polymorphic generation).
filterCollectSubTypes String collectClassSubTypes == true Controls which classes can collect subtypes (sealed, abstract, *).

Examples

Enable only fields with metadata:


final cap = MacroCapability(
  classFields: true,
  filterClassFieldMetadata: 'JsonKey,MyMeta',
);

Enable constructors + inferred initializers:


final cap = MacroCapability(
  classConstructors: true,
  inspectFieldInitializer: true,
);

Collect all subclasses for a sealed base class:


final cap = MacroCapability(
  collectClassSubTypes: true,
  filterCollectSubTypes: 'sealed',
);