X-Git-Url: https://svn.cri.ensmp.fr/git/linpy.git/blobdiff_plain/288355579f9b2160e341e1d48910a66a0124ab04..4a4d773df0dea3cea63023b8d01f380a0024e25a:/pypol/linear.py

diff --git a/pypol/linear.py b/pypol/linear.py
index 8f73fd3..845fac3 100644
--- a/pypol/linear.py
+++ b/pypol/linear.py
@@ -135,7 +135,7 @@ class Expression:
         return False
 
     def __bool__(self):
-        True
+        return True
 
     def __pos__(self):
         return self
@@ -271,7 +271,7 @@ class Expression:
                 self.constant == other.constant
 
     def __hash__(self):
-        return hash((self._coefficients, self._constant))
+        return hash((tuple(sorted(self._coefficients.items())), self._constant))
 
     def _toint(self):
         lcm = functools.reduce(lambda a, b: a*b // gcd(a, b),
@@ -355,7 +355,7 @@ class Symbol(Expression):
 def symbols(names):
     if isinstance(names, str):
         names = names.replace(',', ' ').split()
-    return (symbol(name) for name in names)
+    return (Symbol(name) for name in names)
 
 
 @_polymorphic_operator