add uuid

cpmpy/expressions/variables.py

@@ -47,6 +47,7 @@
     ==============
 """
 import math
+import uuid
 from collections.abc import Iterable
 import warnings # for deprecation warning
 from functools import reduce
@@ -238,6 +239,7 @@ def __init__(self, lb, ub, name):
         self.lb = lb
         self.ub = ub
         self.name = name
+        self.id = uuid.uuid4()
         self._value = None
 
     def is_bool(self):
@@ -263,9 +265,9 @@ def clear(self):
     def __repr__(self):
         return self.name
 
-    # for sets/dicts. Because names are unique, so is the str repr
+    # for sets/dicts. Because id's are unique, so is the str repr
     def __hash__(self):
-        return hash(self.name)
+        return hash(self.id)
 
 
 class _IntVarImpl(_NumVarImpl):
@@ -286,6 +288,8 @@ def __init__(self, lb, ub, name=None):
 
         super().__init__(int(lb), int(ub), name=name) # explicit cast: can be numpy
 
+
+
     # special casing for intvars (and boolvars)
     def __abs__(self):
         if self.lb >= 0:

cpmpy/solvers/exact.py

@@ -290,7 +290,7 @@ def solver_var(self, cpm_var):
             return self._varmap[cpm_var]
 
         # create if it does not exist
-        revar = str(cpm_var)
+        revar = str(cpm_var) + str(cpm_var.id)
         if isinstance(cpm_var, _BoolVarImpl):
             self.xct_solver.addVariable(revar,0,1)
         elif isinstance(cpm_var, _IntVarImpl):

cpmpy/solvers/gurobi.py

@@ -185,9 +185,9 @@ def solver_var(self, cpm_var):
         if cpm_var not in self._varmap:
             from gurobipy import GRB
             if isinstance(cpm_var, _BoolVarImpl):
-                revar = self.grb_model.addVar(vtype=GRB.BINARY, name=cpm_var.name)
+                revar = self.grb_model.addVar(vtype=GRB.BINARY, name=cpm_var.name+str(cpm_var.id))
             elif isinstance(cpm_var, _IntVarImpl):
-                revar = self.grb_model.addVar(cpm_var.lb, cpm_var.ub, vtype=GRB.INTEGER, name=str(cpm_var))
+                revar = self.grb_model.addVar(cpm_var.lb, cpm_var.ub, vtype=GRB.INTEGER, name=cpm_var.name+str(cpm_var.id))
             else:
                 raise NotImplementedError("Not a known var {}".format(cpm_var))
             self._varmap[cpm_var] = revar

cpmpy/solvers/minizinc.py

@@ -335,15 +335,13 @@ def solver_var(self, cpm_var) -> str:
             # we assume all variables are user variables (because no transforms)
             self.user_vars.add(cpm_var)
             # clean the varname
-            varname = cpm_var.name
-            mzn_var = varname.replace(',', '_').replace('.', '_').replace(' ', '_').replace('[', '_').replace(']', '')
+            varname = cpm_var.name + str(cpm_var.id)
+            mzn_var = varname.replace(',', '_').replace('.', '_').replace(' ', '_').replace('[', '_').replace(']', '').replace('-','_')
 
             #test if the name is a valid minizinc identifier
             if not self.mzn_name_pattern.search(mzn_var):
                 raise MinizincNameException("Minizinc only accept names with alphabetic characters, digits and underscores. "
-                                "First character must be an alphabetic character")
-            if mzn_var in self.keywords:
-                raise MinizincNameException(f"This variable name is a disallowed keyword in MiniZinc: {mzn_var}")
+                                "First character must be an alphabetic character" + mzn_var)
 
             if isinstance(cpm_var, _BoolVarImpl):
                 self.mzn_model.add_string(f"var bool: {mzn_var};\n")

cpmpy/solvers/ortools.py

@@ -243,9 +243,9 @@ def solver_var(self, cpm_var):
         # create if it does not exist
         if cpm_var not in self._varmap:
             if isinstance(cpm_var, _BoolVarImpl):
-                revar = self.ort_model.NewBoolVar(str(cpm_var))
+                revar = self.ort_model.NewBoolVar(str(cpm_var)+str(cpm_var.id))
             elif isinstance(cpm_var, _IntVarImpl):
-                revar = self.ort_model.NewIntVar(cpm_var.lb, cpm_var.ub, str(cpm_var))
+                revar = self.ort_model.NewIntVar(cpm_var.lb, cpm_var.ub, str(cpm_var)+str(cpm_var.id))
             else:
                 raise NotImplementedError("Not a known var {}".format(cpm_var))
             self._varmap[cpm_var] = revar

cpmpy/solvers/pysat.py

@@ -206,9 +206,9 @@ def solver_var(self, cpm_var):
         # work directly on var inside the view
         if isinstance(cpm_var, NegBoolView):
             # just a view, get actual var identifier, return -id
-            return -self.pysat_vpool.id(cpm_var._bv.name)
+            return -self.pysat_vpool.id(cpm_var._bv.name + str(cpm_var.id))
         elif isinstance(cpm_var, _BoolVarImpl):
-            return self.pysat_vpool.id(cpm_var.name)
+            return self.pysat_vpool.id(cpm_var.name + str(cpm_var.id))
         else:
             raise NotImplementedError(f"CPM_pysat: variable {cpm_var} not supported")
 

cpmpy/solvers/z3.py

@@ -195,9 +195,9 @@ def solver_var(self, cpm_var):
             # we assume al variables are user variables (because nested expressions)
             self.user_vars.add(cpm_var)
             if isinstance(cpm_var, _BoolVarImpl):
-                revar = z3.Bool(str(cpm_var))
+                revar = z3.Bool(str(cpm_var) + str(cpm_var.id))
             elif isinstance(cpm_var, _IntVarImpl):
-                revar = z3.Int(str(cpm_var))
+                revar = z3.Int(str(cpm_var) + str(cpm_var.id))
                 # set bounds
                 self.z3_solver.add(revar >= cpm_var.lb)
                 self.z3_solver.add(revar <= cpm_var.ub)