[Python-checkins] python/nondist/peps pep-0302.txt,1.13,1.14

[pje at users.sourceforge.net]

Update of /cvsroot/python/python/nondist/peps
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv18527

Modified Files:
	pep-0302.txt 
Log Message:
Fix specification error that makes it impossible for 'reload()' to work
correctly with PEP 302 module loaders.  See also SF#1029475, and:

http://mail.python.org/pipermail/python-dev/2004-September/048970.html


Index: pep-0302.txt
===================================================================
RCS file: /cvsroot/python/python/nondist/peps/pep-0302.txt,v
retrieving revision 1.13
retrieving revision 1.14
diff -u -d -r1.13 -r1.14
--- pep-0302.txt	2 Jan 2003 18:47:04 -0000	1.13
+++ pep-0302.txt	23 Sep 2004 04:06:40 -0000	1.14
@@ -240,16 +240,22 @@
     The load_module() method has a few responsibilities that it must
     fulfill *before* it runs any code:
 
-    - It must create the module object.  From Python this can be done
+    - It must use the existing module object from sys.modules, if one
+      exists.  (Otherwise, the reload() builtin will not work
+      correctly.)
+
+    - If a module object is not already present in sys.modules, the
+      loader must create a module object.  From Python this can be done
       via the new.module() function, the imp.new_module() function or
       via the module type object; from C with the PyModule_New()
       function or the PyImport_ModuleAdd() function.  The latter also
       does the following step:
 
-    - It must add the module to sys.modules.  This is crucial because
-      the module code may (directly or indirectly) import itself; adding
-      it to sys.modules beforehand prevents unbounded recursion in the
-      worst case and multiple loading in the best.
+    - It must add the module to sys.modules, if it was not already
+      present there.  This is crucial because the module code may 
+      (directly or indirectly) import itself; adding it to sys.modules
+      beforehand prevents unbounded recursion in the worst case and
+      multiple loading in the best.
 
     - The __file__ attribute must be set.  This must be a string, but it
       may be a dummy value, for example "<frozen>".  The privilege of