#10963: More functorial constructions
-------------------------------------+-------------------------------------
Reporter: nthiery | Owner: stumpc5
Type: enhancement | Status: needs_work
Priority: major | Milestone:
Component: categories | Resolution:
Keywords: | Merged in:
Authors: Nicolas M. Thiéry | Reviewers: Simon King
Report Upstream: N/A | Work issues: Reduce startup time
Branch: | by 5%. Avoid "recursion depth
Dependencies: #11224, #8327, | exceeded (ignored)".
#10193, #12895, #14516, #14722, | Commit:
#13589, #14471 | Stopgaps:
-------------------------------------+-------------------------------------
Changes (by SimonKing):
* cc: vbraun, nbruin (added)
Comment:
Hmmmm. It is not as easy as I thought. Therefore I put Volker and Nils on
Cc, because they know a lot more on Python than I do.
By inserting print statements, I verified that with unpatched Sage in the
`MonoDict` example, the eraser is called recursively: When invoking the
eraser for a key K1, the deletion of the key-value pair (K1,K2) results in
calling the eraser for K2 ''before'' the eraser of K1 has finished. Hence,
the order is like this:
- the eraser is called recursively, because a deletion happening inside of
the eraser triggers the call to the next eraser.
- the `RuntimeError` is reported after the last deletion has happened
- after reporting the error, the 1000 nested erasers return one after the
other.
With a tentative patch, I can make the callback function work in a
seemingly good way: The eraser is invoked for a key K1, and by assigning
K2 to a local variable, the key-value pair (K1,K2) can be "safely"
removed. The order is like this:
- one eraser is called, and inside of it a deletion happens.
- the next eraser is only called after when the first eraser returns.
And now comes the big surprise: In the very end, the `RuntimeError` is
still reported! Even though the the inserted print statements show that
the calls are not nested!
--
Ticket URL: <http://trac.sagemath.org/ticket/10963#comment:100>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/groups/opt_out.
