Ticket #11115: trac11115_cached_function_pickling.patch

sage/misc/cachefunc.pyx

@@ -226 +226 @@
     sage: print sage_getdoc(test_pfunc)
        Some documentation
     sage: print sage_getdoc(O.wrapped_method)
-    File: ...
-    (starting at line ...) some doc for a wrapped cython method
+    some doc for a wrapped cython method
+    <BLANKLINE>
     sage: print sage_getsource(O.wrapped_method)
     cpdef test_meth(self,x):
         "some doc for a wrapped cython method"
@@ -262 +262 @@
 ########################################################################
 #       Copyright (C) 2008 William Stein <wstein@gmail.com>
 #                          Mike Hansen <mhansen@gmail.com>
+#                     2011 Simon King <simon.king@uni-jena.de>
 #
 #  Distributed under the terms of the GNU General Public License (GPL)
 #
@@ -271 +272 @@
 import os
 from sage.misc.sageinspect import sage_getfile, sage_getsourcelines
 
+def _cached_function_unpickle(module,name):
+    """
+    Unpickling of cached functions.
+
+    NOTE:
+
+    Pickling and unpickling of cached functions is by importing
+    from the module in which the function is defined.
+
+    INPUT:
+
+    - ``module``: A string, describing the module to import the
+      function from.
+    - ``name``: A string, name of the to-be-imported cached function.
+
+    EXAMPLE::
+
+        sage: type(cunningham_prime_factors)
+        <type 'sage.misc.cachefunc.CachedFunction'>
+        sage: loads(dumps(cunningham_prime_factors)) is cunningham_prime_factors #indirect doctest
+        True
+
+    """
+    return getattr(__import__(module, fromlist=['']),name)
+
 cdef class CachedFunction(object):
     """
     Create a cached version of a function, which only recomputes
@@ -391 +417 @@
             self._argument_fixer = argument_fixer
             self._fix_to_pos = argument_fixer.fix_to_pos
 
+    def __reduce__(self):
+        """
+        Pickling of cached functions.
+
+        TEST::
+
+            sage: type(cunningham_prime_factors)
+            <type 'sage.misc.cachefunc.CachedFunction'>
+            sage: loads(dumps(cunningham_prime_factors)) is cunningham_prime_factors #indirect doctest
+            True
+
+        """
+        return _cached_function_unpickle, (self.__module__, self.__name__)
+
     #########
     ## Introspection
     ##
@@ -411 +451 @@
             sage: I = P*[x,y]
             sage: from sage.misc.sageinspect import sage_getdoc
             sage: print sage_getdoc(I.groebner_basis) # indirect doctest
-            File: sage/rings/polynomial/multi_polynomial_ideal.py (starting at
-            line ...)
+               Return the reduced Groebner basis of this ideal.
             ...
                ALGORITHM: Uses Singular, Magma (if available), Macaulay2 (if
                available), or a toy implementation.