library #lib;
import self as self;
import "dart:core" as core;

abstract class A extends core::Object {
  synthetic constructor •() → self::A
    : super core::Object::•()
    ;
  abstract method foo() → core::int;
}
class B extends self::A {
  synthetic constructor •() → self::B
    : super self::A::•()
    ;
[@vm.procedure-attributes.metadata=hasDynamicUses:false,hasThisUses:false,hasTearOffUses:false]  method foo() → core::int
    return 1;
}
class C extends core::Object implements self::A {
  synthetic constructor •() → self::C
    : super core::Object::•()
    ;
[@vm.procedure-attributes.metadata=hasDynamicUses:false,hasThisUses:false,hasTearOffUses:false]  method foo() → core::int
    return 2;
}
class D extends self::C {
  synthetic constructor •() → self::D
    : super self::C::•()
    ;
}
class E extends core::Object {
  synthetic constructor •() → self::E
    : super core::Object::•()
    ;
[@vm.procedure-attributes.metadata=hasDynamicUses:false,hasThisUses:false,hasTearOffUses:false]  method toString() → core::String
    return "D";
}
[@vm.inferred-type.metadata=#lib::D?]static field self::A dd;
[@vm.inferred-type.metadata=#lib::E?]static field self::E ee = new self::E::•();
static method callerA1([@vm.inferred-type.metadata=!] self::A aa) → void {
  [@vm.inferred-type.metadata=!? (skip check)] aa.{self::A::foo}();
}
static method callerA2([@vm.inferred-type.metadata=#lib::B] self::A aa) → void {
  [@vm.direct-call.metadata=#lib::B::foo] [@vm.inferred-type.metadata=!? (skip check)] aa.{self::A::foo}();
}
static method callerA3({[@vm.inferred-type.metadata=#lib::C] self::A aa = null}) → void {
  [@vm.direct-call.metadata=#lib::C::foo] [@vm.inferred-type.metadata=!? (skip check)] aa.{self::A::foo}();
}
static method callerA4([@vm.inferred-type.metadata=#lib::D?] self::A aa) → void {
  [@vm.direct-call.metadata=#lib::C::foo??] [@vm.inferred-type.metadata=!? (skip check)] aa.{self::A::foo}();
}
static method callerE1([@vm.inferred-type.metadata=dart.core::_OneByteString] dynamic x) → void {
  [@vm.direct-call.metadata=dart.core::_StringBase::toString] [@vm.inferred-type.metadata=!? (skip check)] x.{core::Object::toString}();
}
static method callerE2([@vm.inferred-type.metadata=#lib::E?] dynamic x) → void {
  x.{core::Object::toString}();
}
static method main(core::List<core::String> args) → dynamic {
  self::callerA1(new self::B::•());
  self::callerA1(new self::C::•());
  self::callerA2(new self::B::•());
  self::callerA3(aa: new self::C::•());
  self::callerA4([@vm.inferred-type.metadata=#lib::D?] self::dd);
  self::dd = new self::D::•();
  self::callerE1("abc");
  self::callerE2([@vm.inferred-type.metadata=#lib::E?] self::ee);
}