Trying to solve the 'Explore More' challenge from https://github.com/angular/angular.dart.tutorial/wiki/Introducing-filters-and-services, but I can't find the right approach to a filter which modifies the output. This loops forever because the list is changed by the filter. For now this just prepends an x to each ingredient. This is a placeholde…

multiplier_filter.dart

library multiplier_filter;

import 'package:angular/angular.dart';
import '../recipe.dart';

@NgFilter(name: 'multiplierfilter')
class MultiplierFilter {
  call(recipeList, multiplier) {
    if (recipeList is List && multiplier is int) {
      var result = recipeList.map((recipe) {
        List<String> multiplied = [];
        recipe.ingredients.forEach((ingredient) {
          multiplied.add("x" + ingredient);
        });
        return new Recipe(
            recipe.id,
            recipe.name,
            recipe.category,
            multiplied,
            recipe.directions,
            recipe.rating,
            recipe.imgUrl
        );
      }).toList(growable: false);
      return result;
    }
  }
}