Weaker precondition for registering a new coercion
|Reported by:||nthiery||Owned by:||robertwb|
|Cc:||sage-combinat, robertwb||Merged in:||sage-4.3.alpha0|
|Authors:||Nicolas M. Thiéry||Reviewers:||Robert Bradshaw|
|Report Upstream:||N/A||Work issues:|
Description (last modified by )
With the attached patch, the precondition for registering a new coercion from P to Q with register_coercion becomes:
"no coercion into P has been queried, or no coercion from P to Q has been registered or discovered earlier"
Which is a bit weaker than the previous:
"no coercion into P has been queried"
This should still be quite safe, while covering all the formerly problematic practical use cases coming up in the category code #5981.
Change History (12)
Changed 7 years ago by
comment:10 Changed 7 years ago by
- Merged in set to sage-4.3.alpha0
- Resolution set to fixed
- Status changed from positive_review to closed