using System;
using System.Reflection;
namespace Python.Runtime
{
///
/// Implements the __overloads__ attribute of method objects. This object
/// supports the [] syntax to explicitly select an overload by signature.
///
internal class OverloadMapper : ExtensionType
{
private readonly MethodObject m;
private readonly PyObject? target;
public OverloadMapper(MethodObject m, PyObject? target)
{
this.target = target;
this.m = m;
}
///
/// Implement explicit overload selection using subscript syntax ([]).
///
public static NewReference mp_subscript(BorrowedReference tp, BorrowedReference idx)
{
var self = (OverloadMapper)GetManagedObject(tp)!;
// Note: if the type provides a non-generic method with N args
// and a generic method that takes N params, then we always
// prefer the non-generic version in doing overload selection.
Type[]? types = Runtime.PythonArgsToTypeArray(idx);
if (types == null)
{
return Exceptions.RaiseTypeError("type(s) expected");
}
MethodBase? mi = MethodBinder.MatchSignature(self.m.info, types);
if (mi == null)
{
var e = "No match found for signature";
return Exceptions.RaiseTypeError(e);
}
var mb = new MethodBinding(self.m, self.target) { info = mi };
return mb.Alloc();
}
///
/// OverloadMapper __repr__ implementation.
///
public static NewReference tp_repr(BorrowedReference op)
{
var self = (OverloadMapper)GetManagedObject(op)!;
return self.m.GetDocString();
}
}
}