Ticket 16465: fix graded component of degree 0

sagemath · Jul 9, 2014 · 33395c0 · 33395c0
1 parent 90acf89
commit 33395c0
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/src/sage/combinat/structures/__init__.py b/src/sage/combinat/structures/__init__.py
@@ -139,10 +139,12 @@ def __classcall__(cls, grade=None, *args, **options):
             Compositions of integers
             sage: Compositions(4)
             Compositions of integers of degree 4
+            sage: Compositions(0)
+            Compositions of integers of degree 0
         """
         self = super(Structures, cls).__classcall__(cls, *args, **options)
 
-        if grade and grade in cls.grading_set():
+        if grade is not None and grade in cls.grading_set():
             return self.graded_component(grade)
         else: return self