contextdart 0.1.1

golang's `context.Context` implements in dart

example/example.dart

import 'package:contextdart/contextdart.dart';

class Hello {}

void main() async {
  var ctx = Context.withValue(
    Context.background(),
    "value will put into context",
    key: "some comparable key",
  );

  ctx = Context.withValue(
    ctx,
    Hello(),
  );

  getValueFromContextByKey(ctx);

  getValueFromContextByType(ctx);

  canceledContext(ctx);
}

getValueFromContextByKey(Context ctx) {
  // in deep function;
  var v = ctx.value("some comparable key");
  // ignore: avoid_print
  print(v);
}

getValueFromContextByType(Context ctx) {
  // in deep function;
  var v = ctx.value<Hello>();
  // ignore: avoid_print
  print(v);
}

canceledContext(Context ctx) {
  var cctx = Context.withCancel(ctx);

  // async action
  Future.any([
    cctx.done()!.first,
    Stream.periodic(const Duration(seconds: 1))
        .map((e) => Exception("bomb!"))
        .first,
  ]);

  // cancel cause something like timeout
  cctx.cancel();
}