From fcad35e8be449177fdd3d0f7c8f4f3c7a776b9d3 Mon Sep 17 00:00:00 2001
From: Ignace Bleukx <ignace.bleukx@kuleuven.be>
Date: Thu, 18 Jun 2026 18:28:56 +0200
Subject: [PATCH] slots in numvarimpl

---
 cpmpy/expressions/variables.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/cpmpy/expressions/variables.py b/cpmpy/expressions/variables.py
index 80c93b36e..de4639cae 100644
--- a/cpmpy/expressions/variables.py
+++ b/cpmpy/expressions/variables.py
@@ -320,6 +320,8 @@ class _NumVarImpl(Expression):
     including bounds checking and value management. It should not be instantiated
     directly, but rather through the helper functions :func:`~cpmpy.expressions.variables.intvar` and :func:`~cpmpy.expressions.variables.boolvar`.
     """
+    __slots__ = ('lb', 'ub', 'name', '_value')
+
     def __init__(self, lb: int, ub: int, name: str):
         assert (is_num(lb) and is_num(ub))
         assert (lb <= ub)
@@ -432,6 +434,8 @@ class NegBoolView(_BoolVarImpl):
 
         Do not create this object directly, use the `~` operator instead: `~bv`
     """
+    __slots__ = ('_bv',)
+
     def __init__(self, bv: _BoolVarImpl):
         #assert(isinstance(bv, _BoolVarImpl))
         self._bv = bv