using System;
using System.Collections.Generic;

namespace Python.Runtime
{
 /// <summary>
 /// Compares Python object wrappers by Python object references.
 /// <para>Similar to <see cref="object.ReferenceEquals"/> but for Python objects</para>
 /// </summary>
 [Serializable]
 public sealed class PythonReferenceComparer : IEqualityComparer<PyObject>
 {
 public static PythonReferenceComparer Instance { get; } = new PythonReferenceComparer();
 public bool Equals(PyObject? x, PyObject? y)
 {
 return x?.DangerousGetAddressOrNull() == y?.DangerousGetAddressOrNull();
 }

 public int GetHashCode(PyObject obj) => obj.DangerousGetAddressOrNull().GetHashCode();

 private PythonReferenceComparer() { }
 }
}