DisjointUnionEnumeratedSets should not always define Element and _element_constructor_

[hivert]

When the argument facade is set to True the attributes Element and _element_constructor_ are defined by the class DisjointUnionEnumeratedSets. This is a bad idea because it prevents a super class like a category to define them. The following patch fixes this problem.

CC: @sagetrac-sage-combinat

Component: combinatorics

Keywords: DisjointUnionEnumeratedSets, Element, Cernay2012

Author: Florent Hivert

Reviewer: Nicolas M. Thiéry

Merged: sage-5.0.beta6

Issue created by migration from https://trac.sagemath.org/ticket/10603

[hivert]

comment:1

I leave the patch as needs work because there is some dependency on another non finished patch (#10193).

[hivert]

Dependencies: #10193

[fchapoton]

comment:4

Hello, you should add ticket number #10193 to the first line of the commit message.

[hivert]

Changed keywords from DisjointUnionEnumeratedSets Element to DisjointUnionEnumeratedSets, Element, Cenay2012

[hivert]

Changed keywords from DisjointUnionEnumeratedSets, Element, Cenay2012 to DisjointUnionEnumeratedSets, Element, Cernay2012

[hivert]

comment:7

Removed (trivial) dependency to #10193

[hivert]

Changed dependencies from #10193 to none

[hivert]

Attachment: trac_10603-union_enumset_elconstr_fix-fh.patch.gz

[nthiery]

comment:8

Review done on the Sage-Combinat queue. All test pass. Positive review!

[nthiery]

Changed reviewer from Nicolas Thiéry to Nicolas M. Thiéry

[jdemeyer]

Merged: sage-5.0.beta6