This package provides annotations for generating extensions on records, with multiple sizes, using a template.

Usage

1. Annotate an extension with @RecordExtension(size: ...). The annotated extension is used as a template to generate size record extensions with the number of elements varying from 2 to size.

2. Annotate the elements you would like included in the generated extensions, with @RecordExtensionElement while providing the return type and implementation.

Example:

@RecordExtension(size: 3)
extension MyExtension<T> on MyType<T> {
  @RecordExtensionElement(
    type: 'MyType<({type-params})>'
    implementation: 'return MyType(({elements}));'
  )
  MyType<T> get combine => this;
}

This specifies that the following three (since size: 3 was specified) extensions should be generated:

extension MyExtension2<T$1, T$2> on (MyType<T$1>, MyType<T$2>) {
  MyType<(T$1, T$2)> get combine {
    return MyType(($1, $2));
  }
}

extension MyExtension3<T$1, T$2, T$3> on (MyType<T$1>, MyType<T$2>, MyType<T$3>) {
  MyType<(T$1, T$2, T$3)> get combine {
    return MyType(($1, $2, $3));
  }
}

Additional information

Visit the record_extender package for full usage instructions.