Giter Site home page Giter Site logo

Comments (5)

evant avatar evant commented on July 24, 2024

QueryStream extends Stream so you can already asyncMap on it. But yeah some kind of function like mapTo(collector, mapper) would be useful as you could reuse the same collector everywhere.

from streamqflite.

droidery avatar droidery commented on July 24, 2024

Thanks somehow missed that

from streamqflite.

evant avatar evant commented on July 24, 2024

Planning on adding a collector interface, you can use it with BuiltList like so:

class BuiltListCollector<T>
    implements Collector<T, ListBuilder<T>, BuiltList<T>> {
  const BuiltListCollector();

  @override
  ListBuilder<T> supply(int length) => ListBuilder();

  @override
  void add(ListBuilder<T> accumulator, int index, T element) {
    accumulator.add(element);
  }

  @override
  BuiltList<T> finish(ListBuilder<T> accumulator) => accumulator.build();
}

streamDb.createQuery("MyTable", where: 'name LIKE ?', whereArgs: [query])
    .mapTo(BuiltListCollector(), (row) => MyEntry(row));

Thoughts?

from streamqflite.

droidery avatar droidery commented on July 24, 2024

Neat! Maybe you could also solve this by passing in a fold function instead of a map function then the client doesn't need the collector interface and you can fold into a list, BuiltList builder or single value.

from streamqflite.

evant avatar evant commented on July 24, 2024

Now that dart has extension methods, don't think something like this is very useful, you can do:

extension BuiltListExtension on Stream<LazyQuery> {
  Stream<BuiltList<T>> mapToBuiltList<T>(T mapper(Map<String, dynamic> row)) {
    return this.asyncMap((query) => query()).map((rows) {
      var result = BuiltList<T>().toBuilder();

      for (final row in rows) {
        result.add(mapper(row));
      }

      return result.build();
    });
  }
}

from streamqflite.

Related Issues (7)

Recommend Projects

  • React photo React

    A declarative, efficient, and flexible JavaScript library for building user interfaces.

  • Vue.js photo Vue.js

    🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.

  • Typescript photo Typescript

    TypeScript is a superset of JavaScript that compiles to clean JavaScript output.

  • TensorFlow photo TensorFlow

    An Open Source Machine Learning Framework for Everyone

  • Django photo Django

    The Web framework for perfectionists with deadlines.

  • D3 photo D3

    Bring data to life with SVG, Canvas and HTML. 📊📈🎉

Recommend Topics

  • javascript

    JavaScript (JS) is a lightweight interpreted programming language with first-class functions.

  • web

    Some thing interesting about web. New door for the world.

  • server

    A server is a program made to process requests and deliver data to clients.

  • Machine learning

    Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.

  • Game

    Some thing interesting about game, make everyone happy.

Recommend Org

  • Facebook photo Facebook

    We are working to build community through open source technology. NB: members must have two-factor auth.

  • Microsoft photo Microsoft

    Open source projects and samples from Microsoft.

  • Google photo Google

    Google ❤️ Open Source for everyone.

  • D3 photo D3

    Data-Driven Documents codes.