Fix Symbol.__slots__
[linpy.git] / pypol / linear.py
index 0712e1e..5b2dc80 100644 (file)
@@ -50,6 +50,13 @@ class Expression:
     This class implements linear expressions.
     """
 
+    __slots__ = (
+        '_coefficients',
+        '_constant',
+        '_symbols',
+        '_dimension',
+    )
+
     def __new__(cls, coefficients=None, constant=0):
         if isinstance(coefficients, str):
             if constant:
@@ -355,6 +362,10 @@ class Constant(Expression):
 
 class Symbol(Expression):
 
+    __slots__ = Expression.__slots__ + (
+        '_name',
+    )
+
     def __new__(cls, name):
         if isinstance(name, Symbol):
             name = name.name
@@ -410,6 +421,13 @@ class Polyhedron:
     This class implements polyhedrons.
     """
 
+    __slots__ = (
+        '_equalities',
+        '_inequalities',
+        '_constraints',
+        '_symbols',
+    )
+
     def __new__(cls, equalities=None, inequalities=None):
         if isinstance(equalities, str):
             if inequalities is not None: