namespace Python.Runtime
{
using System;
using System.Diagnostics.Contracts;
///
/// Represents a reference to a Python object, that is tracked by Python's reference counting.
///
[NonCopyable]
ref struct NewReference
{
IntPtr pointer;
[Pure]
public static implicit operator BorrowedReference(in NewReference reference)
=> new BorrowedReference(reference.pointer);
///
/// Returns wrapper around this reference, which now owns
/// the pointer. Sets the original reference to null, as it no longer owns it.
///
public PyObject MoveToPyObject()
{
if (this.IsNull()) throw new NullReferenceException();
var result = new PyObject(this.pointer);
this.pointer = IntPtr.Zero;
return result;
}
/// Moves ownership of this instance to unmanged pointer
public IntPtr DangerousMoveToPointerOrNull()
{
var result = this.pointer;
this.pointer = IntPtr.Zero;
return result;
}
///
/// Removes this reference to a Python object, and sets it to null.
///
public void Dispose()
{
if (this.IsNull())
{
return;
}
Runtime.XDecref(pointer);
pointer = IntPtr.Zero;
}
///
/// Creates from a raw pointer
///
[Pure]
public static NewReference DangerousFromPointer(IntPtr pointer)
=> new NewReference {pointer = pointer};
[Pure]
internal static IntPtr DangerousGetAddress(in NewReference reference)
=> IsNull(reference) ? throw new NullReferenceException() : reference.pointer;
[Pure]
internal static bool IsNull(in NewReference reference)
=> reference.pointer == IntPtr.Zero;
}
///
/// These members can not be directly in type,
/// because this is always passed by value, which we need to avoid.
/// (note this in NewReference vs the usual this NewReference)
///
static class NewReferenceExtensions
{
/// Gets a raw pointer to the Python object
[Pure]
public static IntPtr DangerousGetAddress(this in NewReference reference)
=> NewReference.DangerousGetAddress(reference);
[Pure]
public static bool IsNull(this in NewReference reference)
=> NewReference.IsNull(reference);
}
}