Method cmp

crates/vm/src/builtins/slice.rs:310–350

(
        zelf: &Py<Self>,
        other: &PyObject,
        op: PyComparisonOp,
        vm: &VirtualMachine,
    )

impl Comparable for PySlice {
    fn cmp(
        zelf: &Py<Self>,
        other: &PyObject,
        op: PyComparisonOp,
        vm: &VirtualMachine,
    ) -> PyResult<PyComparisonValue> {
        let other = class_or_notimplemented!(Self, other);

        let ret = match op {
            PyComparisonOp::Lt | PyComparisonOp::Le => None
                .or_else(|| {
                    vm.bool_seq_lt(zelf.start_ref(vm), other.start_ref(vm))
                        .transpose()
                })
                .or_else(|| vm.bool_seq_lt(&zelf.stop, &other.stop).transpose())
                .or_else(|| {
                    vm.bool_seq_lt(zelf.step_ref(vm), other.step_ref(vm))
                        .transpose()
                })
                .unwrap_or_else(|| Ok(op == PyComparisonOp::Le))?,
            PyComparisonOp::Eq | PyComparisonOp::Ne => {
                let eq = vm.identical_or_equal(zelf.start_ref(vm), other.start_ref(vm))?
                    && vm.identical_or_equal(&zelf.stop, &other.stop)?
                    && vm.identical_or_equal(zelf.step_ref(vm), other.step_ref(vm))?;
                if op == PyComparisonOp::Ne { !eq } else { eq }
            }
            PyComparisonOp::Gt | PyComparisonOp::Ge => None
                .or_else(|| {
                    vm.bool_seq_gt(zelf.start_ref(vm), other.start_ref(vm))
                        .transpose()
                })
                .or_else(|| vm.bool_seq_gt(&zelf.stop, &other.stop).transpose())
                .or_else(|| {
                    vm.bool_seq_gt(zelf.step_ref(vm), other.step_ref(vm))
                        .transpose()
                })
                .unwrap_or_else(|| Ok(op == PyComparisonOp::Ge))?,
        };

        Ok(PyComparisonValue::Implemented(ret))
    }
}

impl Representable for PySlice {