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FAQ

Known limitations

Limited supported function types on data builders

Currently, due to limitation in the implementation, only a handful of function signatures are provided out-of-the-box. Check Github for the list of supported function type.

Typical errors

type 'Null' is not a subtype of type 'xxx'

This typically happens if a default value or initial value (via @DesignField(parameter: ...)) is not provided to a non-nullable field type.

Context: 'AstVisitor.visitConstructorSelector' is defined here.

Note that you might need to add this to the pubspec.yaml file (I'm working on a fix to avoid needing this override):

dependency_overrides:
analyzer: ^3.2.0
dart_style: ^2.2.1

If you see errors like:

class ToSourceIgnoringDesignAnnotationsVisitor implements AstVisitor {
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
../../../Dev/flutter/.pub-cache/hosted/pub.dartlang.org/analyzer-3.3.1/lib/dart/ast/ast.dart:405:6: Context: 'AstVisitor.visitConstructorSelector' is defined here.

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