Use except? for _rank

src/sage/matroids/basis_exchange_matroid.pxd

@@ -46,7 +46,7 @@ cdef class BasisExchangeMatroid(Matroid):
     cpdef _move_current_basis(self, X, Y)
 
     cpdef frozenset _max_independent(self, frozenset F)
-    cpdef int _rank(self, frozenset F) except -1
+    cpdef int _rank(self, frozenset F) except? -1
     cpdef frozenset _circuit(self, frozenset F)
     cpdef frozenset _fundamental_circuit(self, frozenset B, e)
     cpdef frozenset _closure(self, frozenset F)

src/sage/matroids/basis_exchange_matroid.pyx

@@ -652,7 +652,7 @@ cdef class BasisExchangeMatroid(Matroid):
         self.__max_independent(self._output, self._input)
         return self.__unpack(self._output)
 
-    cpdef int _rank(self, frozenset F) except -1:
+    cpdef int _rank(self, frozenset F) except? -1:
         """
         Compute the rank of a subset of the groundset.
 

src/sage/matroids/circuit_closures_matroid.pxd

@@ -5,7 +5,7 @@ cdef class CircuitClosuresMatroid(Matroid):
     cdef dict _circuit_closures  # _CC
     cdef int _matroid_rank  # _R
     cpdef frozenset groundset(self)
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1
     cpdef full_rank(self)
     cpdef bint _is_independent(self, frozenset F) noexcept
     cpdef frozenset _max_independent(self, frozenset F)

src/sage/matroids/circuit_closures_matroid.pyx

@@ -179,7 +179,7 @@ cdef class CircuitClosuresMatroid(Matroid):
         """
         return frozenset(self._groundset)
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         """
         Return the rank of a set ``X``.
 

src/sage/matroids/circuits_matroid.pxd

@@ -9,7 +9,7 @@ cdef class CircuitsMatroid(Matroid):
     cdef list _sorted_C_lens
     cdef bint _nsc_defined
     cpdef frozenset groundset(self)
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1
     cpdef full_rank(self)
     cpdef bint _is_independent(self, frozenset X) noexcept
     cpdef frozenset _max_independent(self, frozenset X)

src/sage/matroids/circuits_matroid.pyx

@@ -100,7 +100,7 @@ cdef class CircuitsMatroid(Matroid):
         """
         return self._groundset
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         """
         Return the rank of a set ``X``.
 

src/sage/matroids/flats_matroid.pxd

@@ -8,7 +8,7 @@ cdef class FlatsMatroid(Matroid):
     cdef object _L  # lattice of flats
     cpdef frozenset groundset(self)
 
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1
     cpdef frozenset _closure(self, frozenset X)
     cpdef bint _is_closed(self, frozenset X) noexcept
 

src/sage/matroids/flats_matroid.pyx

@@ -114,7 +114,7 @@ cdef class FlatsMatroid(Matroid):
         """
         return self._groundset
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         """
         Return the rank of a set ``X``.
 

src/sage/matroids/graphic_matroid.pxd

@@ -7,7 +7,7 @@ cdef class GraphicMatroid(Matroid):
     cdef dict _vertex_map
     cdef dict _groundset_edge_map
     cpdef frozenset groundset(self)
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1
     cpdef _vertex_stars(self)
     cpdef _minor(self, contractions, deletions)
     cpdef _has_minor(self, N, bint certificate=*)

src/sage/matroids/graphic_matroid.pyx

@@ -238,7 +238,7 @@ cdef class GraphicMatroid(Matroid):
         """
         return self._groundset
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         """
         Return the rank of a set ``X``.
 

src/sage/matroids/matroid.pxd

@@ -9,7 +9,7 @@ cdef class Matroid(SageObject):
 
     # virtual methods
     cpdef frozenset groundset(self)
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1
 
     # internal methods, assuming verified input
     cpdef frozenset _max_independent(self, frozenset X)

src/sage/matroids/matroid.pyx

@@ -492,7 +492,7 @@ cdef class Matroid(SageObject):
         """
         raise NotImplementedError("subclasses need to implement this")
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         r"""
         Return the rank of a set ``X``.
 
@@ -2339,7 +2339,7 @@ cdef class Matroid(SageObject):
         TESTS::
 
             sage: def r(X):
-            ....:     return -2
+            ....:     return -1
             sage: M = Matroid(groundset=[0,1,2], rank_function=r)
             sage: M.is_valid()
             False

src/sage/matroids/union_matroid.pxd

@@ -5,16 +5,16 @@ cdef class MatroidUnion(Matroid):
     cdef list matroids
     cdef frozenset _groundset
     cpdef frozenset groundset(self)
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1
 
 cdef class MatroidSum(Matroid):
     cdef list summands
     cdef frozenset _groundset
     cpdef frozenset groundset(self)
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1
 
 cdef class PartitionMatroid(Matroid):
     cdef dict p
     cdef frozenset _groundset
     cpdef frozenset groundset(self)
-    cpdef int _rank(self, frozenset X) except -1
+    cpdef int _rank(self, frozenset X) except? -1

src/sage/matroids/union_matroid.pyx

@@ -66,7 +66,7 @@ cdef class MatroidUnion(Matroid):
         """
         return self._groundset
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         r"""
         Return the rank of a set ``X``.
 
@@ -195,7 +195,7 @@ cdef class MatroidSum(Matroid):
         """
         return self._groundset
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         r"""
         Return the rank of a set ``X``.
 
@@ -290,7 +290,7 @@ cdef class PartitionMatroid(Matroid):
         """
         return self._groundset
 
-    cpdef int _rank(self, frozenset X) except -1:
+    cpdef int _rank(self, frozenset X) except? -1:
         r"""
         Return the rank of a set ``X``.