On 28 April 2018 at 18:20, Jeroen Demeyer <J.Demeyer@ugent.be> wrote:

On 2018-04-28 18:26, Paul Moore wrote:

...

""" If a file named filename is not found, the function will look for it in the module search path, sys.path, after first checking for a PEP 302 __loader__ in module_globals, in case the module was imported from a zipfile or other non-filesystem import source. """

Sorry, I should have been more precise. linecache does the following (which is what is in the doc you quoted above):

(1) Look for the filename exactly as given. (2) Look for a loader and call its get_source() method. (3) Look for the filename under all sys.path entries.

The difference between (1) and (3) is when a relative filename is given, typically relative to site-packages. And I'm actually interested in that third case.

So the question is really: should (3) still be tried if __loader__.get_source() returns None?

Well, the docs say it is, so I'd say yes. I guess the docs could be interpreted as saying "if there isn't a loader, go on to (3) otherwise call the loader and stop". But I'd say that if __loader__.get_source() returns None, that should be treated the same as no loader being found. Paul