Refactor PyList to have elements as private field

vm/src/obj/objlist.rs

@@ -11,21 +11,26 @@ use super::objbyteinner;
 use super::objint::PyIntRef;
 use super::objiter;
 use super::objsequence::{
-    get_elements_list, get_item, seq_equal, seq_ge, seq_gt, seq_le, seq_lt, seq_mul, SequenceIndex,
+    get_item, seq_equal, seq_ge, seq_gt, seq_le, seq_lt, seq_mul, SequenceIndex,
 };
 use super::objslice::PySliceRef;
-use super::objtype::{self, PyClassRef};
+use super::objtype::PyClassRef;
 use crate::function::OptionalArg;
 use crate::pyobject::{
-    IdProtocol, PyClassImpl, PyContext, PyIterable, PyObjectRef, PyRef, PyResult, PyValue,
-    TryFromObject, TypeProtocol,
+    IdProtocol, PyArithmaticValue::*, PyClassImpl, PyComparisonValue, PyContext, PyIterable,
+    PyObjectRef, PyRef, PyResult, PyValue, TryFromObject, TypeProtocol,
 };
+use crate::sequence::PySequenceContainer;
 use crate::vm::{ReprGuard, VirtualMachine};
 
+/// Built-in mutable sequence.
+///
+/// If no argument is given, the constructor creates a new empty list.
+/// The argument must be an iterable if specified.
+#[pyclass]
 #[derive(Default)]
 pub struct PyList {
-    // TODO: shouldn't be public
-    pub elements: RefCell<Vec<PyObjectRef>>,
+    elements: RefCell<Vec<PyObjectRef>>,
 }
 
 impl fmt::Debug for PyList {
@@ -49,6 +54,19 @@ impl PyValue for PyList {
     }
 }
 
+// impl PySequenceContainer for PyList {
+//     fn as_slice<'a>(&'a self) -> &'a [PyObjectRef] {
+//         let b = self.elements.borrow();
+//         &b
+//     }
+// }
+
+impl PyList {
+    pub fn elements<'a>(&'a self) -> impl std::ops::Deref<Target = Vec<PyObjectRef>> + 'a {
+        self.elements.borrow()
+    }
+}
+
 impl PyList {
     pub fn get_len(&self) -> usize {
         self.elements.borrow().len()
@@ -130,18 +148,22 @@ struct SortOptions {
 
 pub type PyListRef = PyRef<PyList>;
 
-impl PyListRef {
-    pub fn append(self, x: PyObjectRef, _vm: &VirtualMachine) {
+#[pyimpl]
+impl PyList {
+    #[pymethod]
+    pub fn append(&self, x: PyObjectRef, _vm: &VirtualMachine) {
         self.elements.borrow_mut().push(x);
     }
 
-    fn extend(self, x: PyObjectRef, vm: &VirtualMachine) -> PyResult<()> {
+    #[pymethod]
+    fn extend(&self, x: PyObjectRef, vm: &VirtualMachine) -> PyResult<()> {
         let mut new_elements = vm.extract_elements(&x)?;
         self.elements.borrow_mut().append(&mut new_elements);
         Ok(())
     }
 
-    fn insert(self, position: isize, element: PyObjectRef, _vm: &VirtualMachine) {
+    #[pymethod]
+    fn insert(&self, position: isize, element: PyObjectRef, _vm: &VirtualMachine) {
         let mut vec = self.elements.borrow_mut();
         let vec_len = vec.len().to_isize().unwrap();
         // This unbounded position can be < 0 or > vec.len()
@@ -155,76 +177,88 @@ impl PyListRef {
         vec.insert(position, element.clone());
     }
 
-    fn add(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        if objtype::isinstance(&other, &vm.ctx.list_type()) {
-            let e1 = self.elements.borrow();
-            let e2 = get_elements_list(&other);
+    #[pymethod(name = "__add__")]
+    fn add(&self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        if let Some(other) = other.payload_if_subclass::<PyList>(vm) {
+            let e1 = self.elements();
+            let e2 = other.elements();
             let elements = e1.iter().chain(e2.iter()).cloned().collect();
             Ok(vm.ctx.new_list(elements))
         } else {
-            Err(vm.new_type_error(format!("Cannot add {} and {}", self.as_object(), other)))
+            Err(vm.new_type_error(format!(
+                "Cannot add {} and {}",
+                Self::class(vm).name,
+                other.class().name
+            )))
         }
     }
 
-    fn iadd(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+    #[pymethod(name = "__iadd__")]
+    fn iadd(zelf: PyRef<Self>, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
         if let Ok(new_elements) = vm.extract_elements(&other) {
             let mut e = new_elements;
-            self.elements.borrow_mut().append(&mut e);
-            Ok(self.into_object())
+            zelf.elements.borrow_mut().append(&mut e);
+            Ok(zelf.into_object())
         } else {
             Ok(vm.ctx.not_implemented())
         }
     }
 
-    fn bool(self, _vm: &VirtualMachine) -> bool {
+    #[pymethod(name = "__bool__")]
+    fn bool(&self, _vm: &VirtualMachine) -> bool {
         !self.elements.borrow().is_empty()
     }
 
-    fn clear(self, _vm: &VirtualMachine) {
+    #[pymethod]
+    fn clear(&self, _vm: &VirtualMachine) {
         self.elements.borrow_mut().clear();
     }
 
-    fn copy(self, vm: &VirtualMachine) -> PyObjectRef {
+    #[pymethod]
+    fn copy(&self, vm: &VirtualMachine) -> PyObjectRef {
         vm.ctx.new_list(self.elements.borrow().clone())
     }
 
-    fn len(self, _vm: &VirtualMachine) -> usize {
+    #[pymethod(name = "__len__")]
+    fn len(&self, _vm: &VirtualMachine) -> usize {
         self.elements.borrow().len()
     }
 
-    fn sizeof(self, _vm: &VirtualMachine) -> usize {
+    #[pymethod(name = "__sizeof__")]
+    fn sizeof(&self, _vm: &VirtualMachine) -> usize {
         size_of::<Self>() + self.elements.borrow().capacity() * size_of::<PyObjectRef>()
     }
 
-    fn reverse(self, _vm: &VirtualMachine) {
+    #[pymethod]
+    fn reverse(&self, _vm: &VirtualMachine) {
         self.elements.borrow_mut().reverse();
     }
-    fn reversed(self, _vm: &VirtualMachine) -> PyListReverseIterator {
-        let final_position = self.elements.borrow().len();
+
+    #[pymethod(name = "__reversed__")]
+    fn reversed(zelf: PyRef<Self>, _vm: &VirtualMachine) -> PyListReverseIterator {
+        let final_position = zelf.elements.borrow().len();
         PyListReverseIterator {
             position: Cell::new(final_position),
-            list: self,
+            list: zelf,
         }
     }
 
-    fn getitem(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        get_item(
-            vm,
-            self.as_object(),
-            &self.elements.borrow(),
-            needle.clone(),
-        )
+    #[pymethod(name = "__getitem__")]
+    fn getitem(zelf: PyRef<Self>, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        get_item(vm, zelf.as_object(), &zelf.elements(), needle.clone())
     }
 
-    fn iter(self, _vm: &VirtualMachine) -> PyListIterator {
+    #[pymethod(name = "__iter__")]
+    fn iter(zelf: PyRef<Self>, _vm: &VirtualMachine) -> PyListIterator {
         PyListIterator {
             position: Cell::new(0),
-            list: self,
+            list: zelf,
         }
     }
 
+    #[pymethod(name = "__setitem__")]
     fn setitem(
-        self,
+        &self,
         subscript: SequenceIndex,
         value: PyObjectRef,
         vm: &VirtualMachine,
@@ -240,7 +274,7 @@ impl PyListRef {
         }
     }
 
-    fn setindex(self, index: i32, value: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+    fn setindex(&self, index: i32, value: PyObjectRef, vm: &VirtualMachine) -> PyResult {
         if let Some(pos_index) = self.get_pos(index) {
             self.elements.borrow_mut()[pos_index] = value;
             Ok(vm.get_none())
@@ -249,7 +283,7 @@ impl PyListRef {
         }
     }
 
-    fn setslice(self, slice: PySliceRef, sec: PyIterable, vm: &VirtualMachine) -> PyResult {
+    fn setslice(&self, slice: PySliceRef, sec: PyIterable, vm: &VirtualMachine) -> PyResult {
         let step = slice.step_index(vm)?.unwrap_or_else(BigInt::one);
 
         if step.is_zero() {
@@ -303,7 +337,7 @@ impl PyListRef {
         }
     }
 
-    fn _set_slice(self, range: Range<usize>, sec: PyIterable, vm: &VirtualMachine) -> PyResult {
+    fn _set_slice(&self, range: Range<usize>, sec: PyIterable, vm: &VirtualMachine) -> PyResult {
         // consume the iter, we  need it's size
         // and if it's going to fail we want that to happen *before* we start modifing
         let items: Result<Vec<PyObjectRef>, _> = sec.iter(vm)?.collect();
@@ -316,7 +350,7 @@ impl PyListRef {
     }
 
     fn _set_stepped_slice(
-        self,
+        &self,
         range: Range<usize>,
         step: usize,
         sec: PyIterable,
@@ -358,7 +392,7 @@ impl PyListRef {
     }
 
     fn _set_stepped_slice_reverse(
-        self,
+        &self,
         range: Range<usize>,
         step: usize,
         sec: PyIterable,
@@ -400,7 +434,7 @@ impl PyListRef {
         }
     }
 
-    fn _replace_indexes<I>(self, indexes: I, items: &[PyObjectRef])
+    fn _replace_indexes<I>(&self, indexes: I, items: &[PyObjectRef])
     where
         I: Iterator<Item = usize>,
     {
@@ -412,10 +446,11 @@ impl PyListRef {
         }
     }
 
-    fn repr(self, vm: &VirtualMachine) -> PyResult<String> {
-        let s = if let Some(_guard) = ReprGuard::enter(self.as_object()) {
-            let mut str_parts = Vec::with_capacity(self.elements.borrow().len());
-            for elem in self.elements.borrow().iter() {
+    #[pymethod(name = "__repr__")]
+    fn repr(zelf: PyRef<Self>, vm: &VirtualMachine) -> PyResult<String> {
+        let s = if let Some(_guard) = ReprGuard::enter(zelf.as_object()) {
+            let mut str_parts = Vec::with_capacity(zelf.elements.borrow().len());
+            for elem in zelf.elements.borrow().iter() {
                 let s = vm.to_repr(elem)?;
                 str_parts.push(s.as_str().to_string());
             }
@@ -426,30 +461,35 @@ impl PyListRef {
         Ok(s)
     }
 
-    fn hash(self, vm: &VirtualMachine) -> PyResult<()> {
+    #[pymethod(name = "__hash__")]
+    fn hash(&self, vm: &VirtualMachine) -> PyResult<()> {
         Err(vm.new_type_error("unhashable type".to_string()))
     }
 
-    fn mul(self, counter: isize, vm: &VirtualMachine) -> PyObjectRef {
-        let new_elements = seq_mul(&self.elements.borrow().as_slice(), counter)
+    #[pymethod(name = "__mul__")]
+    fn mul(&self, counter: isize, vm: &VirtualMachine) -> PyObjectRef {
+        let new_elements = seq_mul(&self.elements().as_slice(), counter)
             .cloned()
             .collect();
         vm.ctx.new_list(new_elements)
     }
 
-    fn rmul(self, counter: isize, vm: &VirtualMachine) -> PyObjectRef {
+    #[pymethod(name = "__rmul__")]
+    fn rmul(&self, counter: isize, vm: &VirtualMachine) -> PyObjectRef {
         self.mul(counter, &vm)
     }
 
-    fn imul(self, counter: isize, _vm: &VirtualMachine) -> Self {
-        let new_elements = seq_mul(&self.elements.borrow().as_slice(), counter)
+    #[pymethod(name = "__imul__")]
+    fn imul(zelf: PyRef<Self>, counter: isize, _vm: &VirtualMachine) -> PyRef<Self> {
+        let new_elements = seq_mul(&zelf.elements().as_slice(), counter)
             .cloned()
             .collect();
-        self.elements.replace(new_elements);
-        self
+        zelf.elements.replace(new_elements);
+        zelf
     }
 
-    fn count(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<usize> {
+    #[pymethod]
+    fn count(&self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<usize> {
         let mut count: usize = 0;
         for element in self.elements.borrow().iter() {
             if vm.identical_or_equal(element, &needle)? {
@@ -459,7 +499,8 @@ impl PyListRef {
         Ok(count)
     }
 
-    fn contains(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<bool> {
+    #[pymethod(name = "__contains__")]
+    fn contains(&self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<bool> {
         for element in self.elements.borrow().iter() {
             if vm.identical_or_equal(element, &needle)? {
                 return Ok(true);
@@ -469,7 +510,8 @@ impl PyListRef {
         Ok(false)
     }
 
-    fn index(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<usize> {
+    #[pymethod]
+    fn index(&self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<usize> {
         for (index, element) in self.elements.borrow().iter().enumerate() {
             if vm.identical_or_equal(element, &needle)? {
                 return Ok(index);
@@ -479,7 +521,8 @@ impl PyListRef {
         Err(vm.new_value_error(format!("'{}' is not in list", needle_str.as_str())))
     }
 
-    fn pop(self, i: OptionalArg<isize>, vm: &VirtualMachine) -> PyResult {
+    #[pymethod]
+    fn pop(&self, i: OptionalArg<isize>, vm: &VirtualMachine) -> PyResult {
         let mut i = i.into_option().unwrap_or(-1);
         let mut elements = self.elements.borrow_mut();
         if i < 0 {
@@ -494,7 +537,8 @@ impl PyListRef {
         }
     }
 
-    fn remove(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<()> {
+    #[pymethod]
+    fn remove(&self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<()> {
         let mut ri: Option<usize> = None;
         for (index, element) in self.elements.borrow().iter().enumerate() {
             if vm.identical_or_equal(element, &needle)? {
@@ -512,86 +556,100 @@ impl PyListRef {
         }
     }
 
-    fn eq(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        let value = if self.as_object().is(&other) {
-            vm.new_bool(true)
-        } else if objtype::isinstance(&other, &vm.ctx.list_type()) {
-            vm.new_bool(self.inner_eq(&other, vm)?)
+    #[pymethod(name = "__eq__")]
+    fn eq(
+        zelf: PyRef<Self>,
+        other: PyObjectRef,
+        vm: &VirtualMachine,
+    ) -> PyResult<PyComparisonValue> {
+        let value = if zelf.as_object().is(&other) {
+            Implemented(true)
+        } else if let Some(other) = other.payload_if_subclass::<PyList>(vm) {
+            Implemented(seq_equal(
+                vm,
+                &zelf.elements().as_slice(),
+                &other.elements().as_slice(),
+            )?)
         } else {
-            vm.ctx.not_implemented()
+            NotImplemented
         };
         Ok(value)
     }
 
-    fn ne(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        let value = if self.as_object().is(&other) {
-            vm.new_bool(false)
-        } else if objtype::isinstance(&other, &vm.ctx.list_type()) {
-            vm.new_bool(!self.inner_eq(&other, vm)?)
-        } else {
-            vm.ctx.not_implemented()
-        };
-        Ok(value)
+    #[pymethod(name = "__ne__")]
+    fn ne(
+        zelf: PyRef<Self>,
+        other: PyObjectRef,
+        vm: &VirtualMachine,
+    ) -> PyResult<PyComparisonValue> {
+        Ok(PyList::eq(zelf, other, vm)?.map(|v| !v))
     }
 
-    fn inner_eq(self, other: &PyObjectRef, vm: &VirtualMachine) -> PyResult<bool> {
-        let zelf = self.elements.borrow();
-        let other = get_elements_list(other);
-        seq_equal(vm, &zelf.as_slice(), &other.as_slice())
-    }
-
-    fn lt(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        if objtype::isinstance(&other, &vm.ctx.list_type()) {
-            let zelf = self.elements.borrow();
-            let other = get_elements_list(&other);
-            let res = seq_lt(vm, &zelf.as_slice(), &other.as_slice())?;
+    #[pymethod(name = "__lt__")]
+    fn lt(&self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        if let Some(other) = other.payload_if_subclass::<PyList>(vm) {
+            let res = seq_lt(
+                vm,
+                &self.elements().as_slice(),
+                &other.elements().as_slice(),
+            )?;
             Ok(vm.new_bool(res))
         } else {
             Ok(vm.ctx.not_implemented())
         }
     }
 
-    fn gt(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        if objtype::isinstance(&other, &vm.ctx.list_type()) {
-            let zelf = self.elements.borrow();
-            let other = get_elements_list(&other);
-            let res = seq_gt(vm, &zelf.as_slice(), &other.as_slice())?;
+    #[pymethod(name = "__gt__")]
+    fn gt(&self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        if let Some(other) = other.payload_if_subclass::<PyList>(vm) {
+            let res = seq_gt(
+                vm,
+                &self.elements().as_slice(),
+                &other.elements().as_slice(),
+            )?;
             Ok(vm.new_bool(res))
         } else {
             Ok(vm.ctx.not_implemented())
         }
     }
 
-    fn ge(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        if objtype::isinstance(&other, &vm.ctx.list_type()) {
-            let zelf = self.elements.borrow();
-            let other = get_elements_list(&other);
-            let res = seq_ge(vm, &zelf.as_slice(), &other.as_slice())?;
+    #[pymethod(name = "__ge__")]
+    fn ge(&self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        if let Some(other) = other.payload_if_subclass::<PyList>(vm) {
+            let res = seq_ge(
+                vm,
+                &self.elements().as_slice(),
+                &other.elements().as_slice(),
+            )?;
             Ok(vm.new_bool(res))
         } else {
             Ok(vm.ctx.not_implemented())
         }
     }
 
-    fn le(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
-        if objtype::isinstance(&other, &vm.ctx.list_type()) {
-            let zelf = self.elements.borrow();
-            let other = get_elements_list(&other);
-            let res = seq_le(vm, &zelf.as_slice(), &other.as_slice())?;
+    #[pymethod(name = "__le__")]
+    fn le(&self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        if let Some(other) = other.payload_if_subclass::<PyList>(vm) {
+            let res = seq_le(
+                vm,
+                &self.elements().as_slice(),
+                &other.elements().as_slice(),
+            )?;
             Ok(vm.new_bool(res))
         } else {
             Ok(vm.ctx.not_implemented())
         }
     }
 
-    fn delitem(self, subscript: SequenceIndex, vm: &VirtualMachine) -> PyResult<()> {
+    #[pymethod(name = "__delitem__")]
+    fn delitem(&self, subscript: SequenceIndex, vm: &VirtualMachine) -> PyResult<()> {
         match subscript {
             SequenceIndex::Int(index) => self.delindex(index, vm),
             SequenceIndex::Slice(slice) => self.delslice(slice, vm),
         }
     }
 
-    fn delindex(self, index: i32, vm: &VirtualMachine) -> PyResult<()> {
+    fn delindex(&self, index: i32, vm: &VirtualMachine) -> PyResult<()> {
         if let Some(pos_index) = self.get_pos(index) {
             self.elements.borrow_mut().remove(pos_index);
             Ok(())
@@ -600,7 +658,7 @@ impl PyListRef {
         }
     }
 
-    fn delslice(self, slice: PySliceRef, vm: &VirtualMachine) -> PyResult<()> {
+    fn delslice(&self, slice: PySliceRef, vm: &VirtualMachine) -> PyResult<()> {
         let start = slice.start_index(vm)?;
         let stop = slice.stop_index(vm)?;
         let step = slice.step_index(vm)?.unwrap_or_else(BigInt::one);
@@ -669,11 +727,11 @@ impl PyListRef {
         }
     }
 
-    fn _del_slice(self, range: Range<usize>) {
+    fn _del_slice(&self, range: Range<usize>) {
         self.elements.borrow_mut().drain(range);
     }
 
-    fn _del_stepped_slice(self, range: Range<usize>, step: usize) {
+    fn _del_stepped_slice(&self, range: Range<usize>, step: usize) {
         // no easy way to delete stepped indexes so here is what we'll do
         let mut deleted = 0;
         let mut elements = self.elements.borrow_mut();
@@ -694,7 +752,7 @@ impl PyListRef {
         elements.drain((range.end - deleted)..range.end);
     }
 
-    fn _del_stepped_slice_reverse(self, range: Range<usize>, step: usize) {
+    fn _del_stepped_slice_reverse(&self, range: Range<usize>, step: usize) {
         // no easy way to delete stepped indexes so here is what we'll do
         let mut deleted = 0;
         let mut elements = self.elements.borrow_mut();
@@ -715,7 +773,8 @@ impl PyListRef {
         elements.drain(range.start..(range.start + deleted));
     }
 
-    fn sort(self, options: SortOptions, vm: &VirtualMachine) -> PyResult<()> {
+    #[pymethod]
+    fn sort(&self, options: SortOptions, vm: &VirtualMachine) -> PyResult<()> {
         // replace list contents with [] for duration of sort.
         // this prevents keyfunc from messing with the list and makes it easy to
         // check if it tries to append elements to it.
@@ -729,20 +788,21 @@ impl PyListRef {
 
         Ok(())
     }
-}
 
-fn list_new(
-    cls: PyClassRef,
-    iterable: OptionalArg<PyObjectRef>,
-    vm: &VirtualMachine,
-) -> PyResult<PyListRef> {
-    let elements = if let OptionalArg::Present(iterable) = iterable {
-        vm.extract_elements(&iterable)?
-    } else {
-        vec![]
-    };
+    #[pyslot(new)]
+    fn list_new(
+        cls: PyClassRef,
+        iterable: OptionalArg<PyObjectRef>,
+        vm: &VirtualMachine,
+    ) -> PyResult<PyListRef> {
+        let elements = if let OptionalArg::Present(iterable) = iterable {
+            vm.extract_elements(&iterable)?
+        } else {
+            vec![]
+        };
 
-    PyList::from(elements).into_ref_with_type(vm, cls)
+        PyList::from(elements).into_ref_with_type(vm, cls)
+    }
 }
 
 fn quicksort(
@@ -875,51 +935,9 @@ impl PyListReverseIterator {
     }
 }
 
-#[rustfmt::skip] // to avoid line splitting
 pub fn init(context: &PyContext) {
     let list_type = &context.types.list_type;
-
-    let list_doc = "Built-in mutable sequence.\n\n\
-                    If no argument is given, the constructor creates a new empty list.\n\
-                    The argument must be an iterable if specified.";
-
-    extend_class!(context, list_type, {
-        "__sizeof__" => context.new_rustfunc(PyListRef::sizeof),
-        "__add__" => context.new_rustfunc(PyListRef::add),
-        "__iadd__" => context.new_rustfunc(PyListRef::iadd),
-        "__bool__" => context.new_rustfunc(PyListRef::bool),
-        "__contains__" => context.new_rustfunc(PyListRef::contains),
-        "__delitem__" => context.new_rustfunc(PyListRef::delitem),
-        "__eq__" => context.new_rustfunc(PyListRef::eq),
-        "__ne__" => context.new_rustfunc(PyListRef::ne),
-        "__lt__" => context.new_rustfunc(PyListRef::lt),
-        "__gt__" => context.new_rustfunc(PyListRef::gt),
-        "__le__" => context.new_rustfunc(PyListRef::le),
-        "__ge__" => context.new_rustfunc(PyListRef::ge),
-        "__getitem__" => context.new_rustfunc(PyListRef::getitem),
-        "__iter__" => context.new_rustfunc(PyListRef::iter),
-        "__setitem__" => context.new_rustfunc(PyListRef::setitem),
-        "__reversed__" => context.new_rustfunc(PyListRef::reversed),
-        "__mul__" => context.new_rustfunc(PyListRef::mul),
-        "__rmul__" => context.new_rustfunc(PyListRef::rmul),
-        "__imul__" => context.new_rustfunc(PyListRef::imul),
-        "__len__" => context.new_rustfunc(PyListRef::len),
-        (slot new) => list_new,
-        "__repr__" => context.new_rustfunc(PyListRef::repr),
-        "__hash__" => context.new_rustfunc(PyListRef::hash),
-        "__doc__" => context.new_str(list_doc.to_string()),
-        "append" => context.new_rustfunc(PyListRef::append),
-        "clear" => context.new_rustfunc(PyListRef::clear),
-        "copy" => context.new_rustfunc(PyListRef::copy),
-        "count" => context.new_rustfunc(PyListRef::count),
-        "extend" => context.new_rustfunc(PyListRef::extend),
-        "index" => context.new_rustfunc(PyListRef::index),
-        "insert" => context.new_rustfunc(PyListRef::insert),
-        "reverse" => context.new_rustfunc(PyListRef::reverse),
-        "sort" => context.new_rustfunc(PyListRef::sort),
-        "pop" => context.new_rustfunc(PyListRef::pop),
-        "remove" => context.new_rustfunc(PyListRef::remove)
-    });
+    PyList::extend_class(context, list_type);
 
     PyListIterator::extend_class(context, &context.types.listiterator_type);
     PyListReverseIterator::extend_class(context, &context.types.listreverseiterator_type);

vm/src/obj/objsequence.rs

@@ -1,6 +1,6 @@
 use std::cell::RefCell;
 use std::marker::Sized;
-use std::ops::{Deref, DerefMut, Range};
+use std::ops::Range;
 
 use num_bigint::{BigInt, ToBigInt};
 use num_traits::{One, Signed, ToPrimitive, Zero};
@@ -389,27 +389,6 @@ pub fn seq_mul(seq: &impl SimpleSeq, repetitions: isize) -> SeqMul {
     }
 }
 
-pub fn get_elements_cell<'a>(obj: &'a PyObjectRef) -> &'a RefCell<Vec<PyObjectRef>> {
-    if let Some(list) = obj.payload::<PyList>() {
-        return &list.elements;
-    }
-    panic!("Cannot extract elements from non-sequence");
-}
-
-pub fn get_elements_list<'a>(obj: &'a PyObjectRef) -> impl Deref<Target = Vec<PyObjectRef>> + 'a {
-    if let Some(list) = obj.payload::<PyList>() {
-        return list.elements.borrow();
-    }
-    panic!("Cannot extract elements from non-sequence");
-}
-
-pub fn get_mut_elements<'a>(obj: &'a PyObjectRef) -> impl DerefMut<Target = Vec<PyObjectRef>> + 'a {
-    if let Some(list) = obj.payload::<PyList>() {
-        return list.elements.borrow_mut();
-    }
-    panic!("Cannot extract elements from non-sequence");
-}
-
 //Check if given arg could be used with PySliceableSequence.get_slice_range()
 pub fn is_valid_slice_arg(
     arg: OptionalArg<PyObjectRef>,

vm/src/obj/objtuple.rs

@@ -278,7 +278,6 @@ impl PyTupleIterator {
     }
 }
 
-#[rustfmt::skip] // to avoid line splitting
 pub fn init(context: &PyContext) {
     let tuple_type = &context.types.tuple_type;
     PyTuple::extend_class(context, tuple_type);

vm/src/py_serde.rs

@@ -5,7 +5,8 @@ use serde::de::{DeserializeSeed, Visitor};
 use serde::ser::{Serialize, SerializeMap, SerializeSeq};
 
 use crate::obj::{
-    objbool, objdict::PyDictRef, objfloat, objint, objsequence, objstr, objtuple::PyTuple, objtype,
+    objbool, objdict::PyDictRef, objfloat, objint, objlist::PyList, objstr, objtuple::PyTuple,
+    objtype,
 };
 use crate::pyobject::{IdProtocol, ItemProtocol, PyObjectRef, TypeProtocol};
 use crate::VirtualMachine;
@@ -86,9 +87,8 @@ impl<'s> serde::Serialize for PyObjectSerializer<'s> {
             } else {
                 serializer.serialize_i64(v.to_i64().ok_or_else(int_too_large)?)
             }
-        } else if objtype::isinstance(self.pyobject, &self.vm.ctx.list_type()) {
-            let elements = objsequence::get_elements_list(self.pyobject);
-            serialize_seq_elements(serializer, &elements)
+        } else if let Some(list) = self.pyobject.payload_if_subclass::<PyList>(self.vm) {
+            serialize_seq_elements(serializer, &list.elements())
         } else if let Some(tuple) = self.pyobject.payload_if_subclass::<PyTuple>(self.vm) {
             serialize_seq_elements(serializer, tuple.as_slice())
         } else if objtype::isinstance(self.pyobject, &self.vm.ctx.dict_type()) {

vm/src/stdlib/subprocess.rs

@@ -8,7 +8,6 @@ use subprocess;
 use crate::function::OptionalArg;
 use crate::obj::objbytes::PyBytesRef;
 use crate::obj::objlist::PyListRef;
-use crate::obj::objsequence;
 use crate::obj::objstr::{self, PyStringRef};
 use crate::obj::objtype::PyClassRef;
 use crate::pyobject::{Either, IntoPyObject, PyObjectRef, PyRef, PyResult, PyValue};
@@ -107,7 +106,8 @@ impl PopenRef {
         let stderr = convert_redirection(args.stderr, vm)?;
         let command_list = match &args.args {
             Either::A(command) => vec![command.as_str().to_string()],
-            Either::B(command_list) => objsequence::get_elements_list(command_list.as_object())
+            Either::B(command_list) => command_list
+                .elements()
                 .iter()
                 .map(|x| objstr::get_value(x))
                 .collect(),

vm/src/vm.rs

@@ -33,8 +33,8 @@ use crate::obj::objfunction::{PyFunction, PyMethod};
 use crate::obj::objgenerator::PyGenerator;
 use crate::obj::objint::PyInt;
 use crate::obj::objiter;
+use crate::obj::objlist::PyList;
 use crate::obj::objmodule::{self, PyModule};
-use crate::obj::objsequence;
 use crate::obj::objstr::{PyString, PyStringRef};
 use crate::obj::objtuple::{PyTuple, PyTupleRef};
 use crate::obj::objtype::{self, PyClassRef};
@@ -913,7 +913,10 @@ impl VirtualMachine {
                 .map(|obj| T::try_from_object(self, obj.clone()))
                 .collect()
         } else if cls.is(&self.ctx.list_type()) {
-            objsequence::get_elements_list(value)
+            value
+                .payload::<PyList>()
+                .unwrap()
+                .elements()
                 .iter()
                 .map(|obj| T::try_from_object(self, obj.clone()))
                 .collect()