co19/LanguageFeatures/Extension-types/static_analysis_extension_types_A24_t02

[scheglov]

extension type const ET2<T>(int id) {
  const ET2.c1() : this(0);
<cut>

  ET2.c1.expectStaticType<Exactly<ET2<dynamic> Function()>>();

Why is it ET2<dynamic> Function()?

For classes we keep constructor of generic classes uninstantiated.

class A<T> {
  A.named() {
    print('T: $T');
  }
}

main() {
  const x = A.named;
  x<int>();
  x<double>();
}

This code prints

T: int
T: double

@eernstg

[eernstg]

Agreed, it should be ET2.c1.expectStaticType<Exactly<ET2<X> Function<X>()>>();, cf. this rule (except that the return type of name$tearoff should be C<typeArgs> rather than a plain C).