""" Wrapper for Singular's Rings AUTHOR: - Martin Albrecht (2009-07): initial implementation """ #***************************************************************************** # Copyright (C) 2009 Martin Albrecht <[email protected]> # # Distributed under the terms of the GNU General Public License (GPL) # http://www.gnu.org/licenses/ #***************************************************************************** from sage.libs.singular.decl cimport ring # To work with singular rings, you need to balance singular_ring_new with # singular_ring_delete or singular_ring_reference with # singular_ring_delete. That is, either use one of the two patterns: # # cdef class myclass_new(): # cdef ring* myring; # cdef __cinit__(): # self.myring = singular_ring_new(...) # cdef __dealloc__(): # singular_ring_delete(self.myring) # # cdef class myclass_reference(): # cdef ring* refring; # cdef __cinit__(ring* some_ring): # self.refring = singular_ring_reference(some_ring) # cdef __dealloc__(): # singular_ring_delete(self.refring) # # You must not refer to Python/Cython classes in the Cython # destructor, the following is INVALID: # # cdef class myclass_invalid(): # cdef Parent parent; # cdef __cinit__(Parent p): # self.parent = p # cdef __dealloc__(): # do_something_with(self.parent.ring) # segfault # create a new singular ring cdef ring *singular_ring_new(base_ring, n, names, term_order) except NULL # reference an existing ring cdef ring *singular_ring_reference(ring *existing_ring) except NULL # carefully delete a ring once its refcount is zero cdef void singular_ring_delete(ring *doomed)
