PyInterned

stdlib/src/array.rs

@@ -683,7 +683,7 @@ mod array {
         fn typecode(&self, vm: &VirtualMachine) -> PyStrRef {
             vm.ctx
                 .intern_str(self.read().typecode().to_string())
-                .to_str()
+                .to_owned()
         }
 
         #[pyproperty]

vm/src/builtins/bool.rs

@@ -117,7 +117,6 @@ impl PyBool {
             vm.ctx.false_str
         }
         .to_owned()
-        .into_pyref()
     }
 
     #[pymethod(magic)]

vm/src/builtins/code.rs

@@ -104,7 +104,7 @@ impl ConstantBag for PyObjBag<'_> {
     }
 
     fn make_name(&self, name: &str) -> PyStrRef {
-        self.0.intern_str(name).to_str()
+        self.0.intern_str(name).to_owned()
     }
 }
 

vm/src/builtins/str.rs

@@ -230,7 +230,7 @@ impl IntoPyStrRef for &str {
 impl IntoPyStrRef for &'static crate::intern::PyStrInterned {
     #[inline]
     fn into_pystr_ref(self, _vm: &VirtualMachine) -> PyRef<PyStr> {
-        self.to_str()
+        self.to_owned()
     }
 }
 

vm/src/intern.rs

@@ -2,7 +2,7 @@ use crate::{
     builtins::{PyStr, PyTypeRef},
     common::lock::PyRwLock,
     convert::ToPyObject,
-    AsObject, Py, PyExact, PyObject, PyObjectRef, PyRef, PyRefExact,
+    AsObject, Py, PyExact, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, VirtualMachine,
 };
 use std::{
     borrow::{Borrow, ToOwned},
@@ -113,11 +113,84 @@ impl CachedPyStrRef {
     }
 }
 
+pub struct PyInterned<T>
+where
+    T: PyPayload,
+{
+    inner: Py<T>,
+}
+
+impl<T: PyPayload> PyInterned<T> {
+    #[inline]
+    pub fn leak(cache: PyRef<T>) -> &'static Self {
+        unsafe { std::mem::transmute(cache) }
+    }
+
+    #[inline]
+    fn as_ptr(&self) -> *const Py<T> {
+        self as *const _ as *const _
+    }
+
+    #[inline]
+    pub fn to_owned(&'static self) -> PyRef<T> {
+        unsafe { (*(&self as *const _ as *const PyRef<T>)).clone() }
+    }
+
+    #[inline]
+    pub fn to_object(&'static self) -> PyObjectRef {
+        self.to_owned().into()
+    }
+}
+
+impl<T: PyPayload> Borrow<PyObject> for PyInterned<T> {
+    #[inline(always)]
+    fn borrow(&self) -> &PyObject {
+        self.inner.borrow()
+    }
+}
+
+// NOTE: std::hash::Hash of Self and Self::Borrowed *must* be the same
+// This is ok only because PyObject doesn't implement Hash
+impl<T: PyPayload> std::hash::Hash for PyInterned<T> {
+    #[inline(always)]
+    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+        self.get_id().hash(state)
+    }
+}
+
+impl<T: PyPayload> Deref for PyInterned<T> {
+    type Target = Py<T>;
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl<T: PyPayload> PartialEq for PyInterned<T> {
+    #[inline(always)]
+    fn eq(&self, other: &Self) -> bool {
+        std::ptr::eq(self, other)
+    }
+}
+
+impl<T: PyPayload> Eq for PyInterned<T> {}
+
+impl<T: PyPayload + std::fmt::Debug> std::fmt::Debug for PyInterned<T> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Debug::fmt(&**self, f)?;
+        write!(f, "@{:p}", self.as_ptr())
+    }
+}
+
+impl<T: PyPayload> ToPyObject for &'static PyInterned<T> {
+    fn to_pyobject(self, _vm: &VirtualMachine) -> PyObjectRef {
+        self.to_owned().into()
+    }
+}
+
 /// The unique reference of interned PyStr
 /// Always intended to be used as a static reference
-pub struct PyStrInterned {
-    inner: Py<PyStr>,
-}
+pub type PyStrInterned = PyInterned<PyStr>;
 
 impl PyStrInterned {
     /// # Safety
@@ -128,70 +201,8 @@ impl PyStrInterned {
     }
 
     #[inline]
-    fn as_ptr(&self) -> *const Py<PyStr> {
-        self as *const _ as *const _
-    }
-
-    #[inline]
-    pub fn to_owned(&'static self) -> PyRefExact<PyStr> {
-        unsafe { (*(&self as *const _ as *const PyRefExact<PyStr>)).clone() }
-    }
-
-    #[inline]
-    pub fn to_str(&'static self) -> PyRef<PyStr> {
-        self.to_owned().into_pyref()
-    }
-
-    #[inline]
-    pub fn to_object(&'static self) -> PyObjectRef {
-        self.to_str().into()
-    }
-}
-
-impl Borrow<PyObject> for PyStrInterned {
-    #[inline(always)]
-    fn borrow(&self) -> &PyObject {
-        self.inner.borrow()
-    }
-}
-
-// NOTE: std::hash::Hash of Self and Self::Borrowed *must* be the same
-// This is ok only because PyObject doesn't implement Hash
-impl std::hash::Hash for PyStrInterned {
-    #[inline(always)]
-    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
-        self.get_id().hash(state)
-    }
-}
-
-impl Deref for PyStrInterned {
-    type Target = Py<PyStr>;
-    #[inline(always)]
-    fn deref(&self) -> &Self::Target {
-        &self.inner
-    }
-}
-
-impl PartialEq for PyStrInterned {
-    #[inline(always)]
-    fn eq(&self, other: &Self) -> bool {
-        std::ptr::eq(self, other)
-    }
-}
-
-impl Eq for PyStrInterned {}
-
-impl AsRef<str> for PyStrInterned {
-    #[inline(always)]
-    fn as_ref(&self) -> &str {
-        self.as_str()
-    }
-}
-
-impl std::fmt::Debug for PyStrInterned {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        std::fmt::Debug::fmt(self.as_str(), f)?;
-        write!(f, "@{:p}", self.as_ptr())
+    pub fn to_exact(&'static self) -> PyRefExact<PyStr> {
+        unsafe { PyRefExact::new_unchecked(self.to_owned()) }
     }
 }
 
@@ -201,6 +212,13 @@ impl std::fmt::Display for PyStrInterned {
     }
 }
 
+impl AsRef<str> for PyStrInterned {
+    #[inline(always)]
+    fn as_ref(&self) -> &str {
+        self.as_str()
+    }
+}
+
 mod sealed {
     use crate::{
         builtins::PyStr,

vm/src/stdlib/sys.rs

@@ -132,7 +132,7 @@ mod sys {
             } else {
                 "unknown"
             })
-            .to_str()
+            .to_owned()
     }
 
     #[pyattr]
@@ -513,7 +513,7 @@ mod sys {
 
     #[pyfunction]
     fn intern(s: PyRefExact<PyStr>, vm: &VirtualMachine) -> PyRefExact<PyStr> {
-        vm.ctx.intern_str(s).to_owned()
+        vm.ctx.intern_str(s).to_exact()
     }
 
     #[pyattr]

vm/src/vm/context.rs

@@ -80,15 +80,14 @@ impl Context {
 
         let new_str = unsafe { string_pool.intern("__new__", types.str_type.clone()) };
         let slot_new_wrapper = create_object(
-            PyNativeFuncDef::new(PyType::__new__.into_func(), new_str.to_owned().into_pyref())
-                .into_function(),
+            PyNativeFuncDef::new(PyType::__new__.into_func(), new_str.to_owned()).into_function(),
             &types.builtin_function_or_method_type,
         )
         .into();
 
         let true_str = unsafe { string_pool.intern("True", types.str_type.clone()) };
         let false_str = unsafe { string_pool.intern("False", types.str_type.clone()) };
-        let empty_str = unsafe { string_pool.intern("", types.str_type.clone()) }.to_str();
+        let empty_str = unsafe { string_pool.intern("", types.str_type.clone()) }.to_owned();
 
         let context = Context {
             true_value,