library test;
import self as self;
import "dart:async" as asy;
import "dart:core" as core;
import "dart:_internal" as _in;

import "dart:async";

static method main() → dynamic /* futureValueType= dynamic */ /* originally async */ {
  final asy::_Future<dynamic>* :async_future = new asy::_Future::•<dynamic>();
  core::bool* :is_sync = false;
  dynamic :return_value;
  (dynamic) →* dynamic :async_op_then;
  (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
  core::int* :await_jump_var = 0;
  dynamic :await_ctx_var;
  dynamic :saved_try_context_var0;
  function :async_op(dynamic :result_or_exception, dynamic :stack_trace) → dynamic yielding 
    try {
      #L1:
      {
        () →* asy::Future<Null>* f = () → asy::Future<Null>* /* futureValueType= Null */ /* originally async */ {
          final asy::_Future<Null>* :async_future = new asy::_Future::•<Null>();
          core::bool* :is_sync = false;
          FutureOr<Null>* :return_value;
          (dynamic) →* dynamic :async_op_then;
          (core::Object*, core::StackTrace*) →* dynamic :async_op_error;
          core::int* :await_jump_var = 0;
          dynamic :await_ctx_var;
          function :async_op(dynamic :result_or_exception, dynamic :stack_trace) → dynamic yielding 
            try {
              #L2:
              {
                :return_value = null;
                break #L2;
              }
              asy::_completeOnAsyncReturn(:async_future, :return_value, :is_sync);
              return;
            }
            on dynamic catch(dynamic exception, core::StackTrace* stack_trace) {
              asy::_completeOnAsyncError(:async_future, exception, stack_trace, :is_sync);
            }
          :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
          :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
          :async_op(null, null){() →* dynamic};
          :is_sync = true;
          return :async_future;
        };
        asy::Future<dynamic>* y = f(){() →* asy::Future<Null>*};
        asy::Future<core::String*>* z = f(){() →* asy::Future<Null>*};
        [yield] let dynamic #t1 = asy::_awaitHelper(f(){() →* asy::Future<Null>*}, :async_op_then, :async_op_error) in null;
        core::String* s = _in::unsafeCast<Null>(:result_or_exception);
      }
      asy::_completeWithNoFutureOnAsyncReturn(:async_future, :return_value, :is_sync);
      return;
    }
    on dynamic catch(dynamic exception, core::StackTrace* stack_trace) {
      asy::_completeOnAsyncError(:async_future, exception, stack_trace, :is_sync);
    }
  :async_op_then = asy::_asyncThenWrapperHelper(:async_op);
  :async_op_error = asy::_asyncErrorWrapperHelper(:async_op);
  :async_op(null, null){() →* dynamic};
  :is_sync = true;
  return :async_future;
}