質問

According to this test, I can not invoke the method "method" with an argument "list" because argument type is not compatible with the type of the method parameter.

Where I am wrong in my test?

import "dart:mirrors";

void main() {
  var list = new List<String>();
  var listMirror = reflectClass(list.runtimeType);
  // Is "List<String>" subtype of "List<String>"?
  print(listMirror.isSubtypeOf(listMirror));
  // Method with parameter "List<String>"
  var method = (List<String> list) {};
  var closure = reflect(method) as ClosureMirror;
  var function = closure.function;
  var parameter = function.parameters.first;
  // Is "List<String>" subtype of "List<String>"?
  print(parameter.type.isSubtypeOf(listMirror));
  print(listMirror.isSubtypeOf(parameter.type));
  // Invoke method with arg: "List<String>" on param "List<String>"
  method(list);
}

Output:

true
false
false

P.S.

Maybe I not understand something but it still not works.

import "dart:mirrors";

void main() {
  var stringMirror = reflectClass(String);
  // Query "List<int> get codeUnits"
  MethodMirror method = stringMirror.declarations.values
      .where((e) => e.simpleName == #codeUnits).first;

  // List<int>
  var returnType = method.returnType;
  print(returnType);

  // List
  var baseType = reflectClass(List);
  print(baseType);

  // List<int> is List
  print(returnType.isSubtypeOf(baseType));
}

Output:

ClassMirror on 'List'
ClassMirror on 'List'
false
役に立ちましたか?

解決

This line is the culprit:

var listMirror = reflectClass(list.runtimeType);

it returns

ClassMirror on '_GrowableList'

if you use

var listMirror = reflectType(List);

it should work.

What you can when you need to get the type from a value at runtime

var listMirror = reflect(list).type.superinterfaces;
...
listMirror.forEach((e) => print(parameter.type.isSubtypeOf(e)));

depending on the situation you may need to make additional checks with

reflect(list).type.mixin;

If one of these checks is true it is a subtype.

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