From 6ec23dc57252ffe01aa60595fc499f580381e4a9 Mon Sep 17 00:00:00 2001
From: Vivien Maisonneuve <v.maisonneuve@gmail.com>
Date: Fri, 11 Jul 2014 18:29:17 +0200
Subject: [PATCH 1/1] Add abstract class GeometricObject

---
 pypol/coordinates.py |  3 ++-
 pypol/domains.py     | 18 +++++++++++-------
 pypol/geometry.py    | 25 +++++++++++++++++++++++++
 pypol/polyhedra.py   |  7 ++-----
 4 files changed, 40 insertions(+), 13 deletions(-)
 create mode 100644 pypol/geometry.py

diff --git a/pypol/coordinates.py b/pypol/coordinates.py
index d392e37..ceab418 100644
--- a/pypol/coordinates.py
+++ b/pypol/coordinates.py
@@ -4,6 +4,7 @@ import operator
 
 from collections import OrderedDict, Mapping
 
+from .geometry import GeometricObject
 from .linexprs import Symbol
 
 
@@ -78,7 +79,7 @@ class Coordinates:
             yield symbol, func(coordinate1, coordinate2)
 
 
-class Point(Coordinates):
+class Point(Coordinates, GeometricObject):
     """
     This class represents points in space.
     """
diff --git a/pypol/domains.py b/pypol/domains.py
index 255c995..cd118e8 100644
--- a/pypol/domains.py
+++ b/pypol/domains.py
@@ -6,6 +6,7 @@ from fractions import Fraction
 
 from . import islhelper
 from .islhelper import mainctx, libisl, isl_set_basic_sets
+from .geometry import GeometricObject
 from .coordinates import Point
 from .linexprs import Expression, Symbol
 
@@ -17,7 +18,7 @@ __all__ = [
 
 
 @functools.total_ordering
-class Domain:
+class Domain(GeometricObject):
 
     __slots__ = (
         '_polyhedra',
@@ -28,14 +29,14 @@ class Domain:
     def __new__(cls, *polyhedra):
         from .polyhedra import Polyhedron
         if len(polyhedra) == 1:
-            polyhedron = polyhedra[0]
-            if isinstance(polyhedron, str):
-                return cls.fromstring(polyhedron)
-            elif isinstance(polyhedron, Polyhedron):
-                return polyhedron
+            argument = polyhedra[0]
+            if isinstance(argument, str):
+                return cls.fromstring(argument)
+            elif isinstance(argument, GeometricObject):
+                return argument.aspolyhedron()
             else:
                 raise TypeError('argument must be a string '
-                    'or a Polyhedron instance')
+                    'or a GeometricObject instance')
         else:
             for polyhedron in polyhedra:
                 if not isinstance(polyhedron, Polyhedron):
@@ -154,6 +155,9 @@ class Domain:
         islbset = libisl.isl_set_polyhedral_hull(islset)
         return Polyhedron._fromislbasicset(islbset, self.symbols)
 
+    def asdomain(self):
+        return self
+
     def project(self, dims):
         # use to remove certain variables
         islset = self._toislset(self.polyhedra, self.symbols)
diff --git a/pypol/geometry.py b/pypol/geometry.py
new file mode 100644
index 0000000..d1d6770
--- /dev/null
+++ b/pypol/geometry.py
@@ -0,0 +1,25 @@
+
+from abc import ABC, abstractmethod, abstractproperty
+
+
+__all__ = [
+    'GeometricObject',
+]
+
+
+class GeometricObject(ABC):
+
+    @abstractproperty
+    def symbols(self):
+        pass
+
+    @property
+    def dimension(self):
+        return len(self.symbols)
+
+    @abstractmethod
+    def aspolyhedron(self):
+        pass
+
+    def asdomain(self):
+        return self.aspolyhedron()
diff --git a/pypol/polyhedra.py b/pypol/polyhedra.py
index a08213d..2eaa7b5 100644
--- a/pypol/polyhedra.py
+++ b/pypol/polyhedra.py
@@ -6,6 +6,7 @@ import numbers
 from . import islhelper
 
 from .islhelper import mainctx, libisl
+from .geometry import GeometricObject
 from .coordinates import Point
 from .linexprs import Expression, Symbol, Rational
 from .domains import Domain
@@ -33,11 +34,7 @@ class Polyhedron(Domain):
             if inequalities is not None:
                 raise TypeError('too many arguments')
             return cls.fromstring(equalities)
-        elif isinstance(equalities, Polyhedron):
-            if inequalities is not None:
-                raise TypeError('too many arguments')
-            return equalities
-        elif isinstance(equalities, Domain):
+        elif isinstance(equalities, GeometricObject):
             if inequalities is not None:
                 raise TypeError('too many arguments')
             return equalities.aspolyhedron()
-- 
2.20.1