[Python-Dev] PEP 302 and 'reload()'
Phillip J. Eby
pje at telecommunity.com
Wed Sep 8 23:38:32 CEST 2004
It appears to me there is an error in both PEP 302's specification and its
implementation concerning the correct operation of reload(). First, it says:
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
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.
This should probably say that if the module already exists in sys.modules,
it should reuse the existing module object, rather than creating a new
one. Otherwise, 'reload()' cannot fulfill its contract.
Second, the actual implementation of PyImport_ReloadModule doesn't actually
use a loader object, so reload() doesn't work with import hooks at
all. There's an SF bug report for this, and a patch to fix it (that also
adds a test to test_importhooks to ensure that 'reload()' actually invokes
Are there any objections to me fixing either/both of these, and backporting
the bugfix to the 2.3 maintenance branch?
Also, should PyImport_ReloadModule use the import lock? It doesn't
currently, but I'm not clear on why it doesn't.
More information about the Python-Dev