Set factories

[nthiery]

At Sage days 30, a long brainstorm seems to have finalized the design. Here is a excerpt from the documentation:

A set factory F is device, whose goal is to construct parent P which models subsets of a big set S. Typically, the P s are constructed within families obtained by putting a bunch of constraints cons on the elements of the set S. In such a hierarchy of subsets, one needs to have a fine and easy control on the elements construction. That is, one often needs that P constructs elements in a subclass of its usual class for element. On the contrary, one also often needs P to be a facade parent, meaning that P construct element whose actual parent is not P itself.

The role of a set factory is twofold:

• manage a database of constructors for the different parents P = F(cons) depending on the various kinds of constraints cons. Note: currently there is no real support for that. We are gathering use case before fixing the interface.

• ensure that the elements e = P(...) created by the different parents follows a consistent policy concerning their class and parent.

The patch implement this idea while trying to leave as much as possible space for further improvement. In particular, I tried to specify the few possible things about constraints. I'm even not completely sure about add_constraints. Please comment and review.

Florent

CC: @sagetrac-sage-combinat @hivert

Component: combinatorics

Keywords: factories, days30, Cernay2012, days57

Author: Florent Hivert

Branch/Commit: 763f93c

Reviewer: Frédéric Chapoton

Issue created by migration from https://trac.sagemath.org/ticket/10194

[nthiery]

comment:1

Patch under development on the Sage-Combinat patch server.

[hivert]

Description changed:

--- 
+++ 
@@ -1 +1,3 @@
+At Sage days 30, a long brainstorm seems to have finalized the design. I'm writing a patch on sage combinat queue.

+  

[hivert]

Changed keywords from none to factories, days30

[hivert]

Changed keywords from factories, days30 to factories, days30, Cernay2012

[hivert]

Description changed:

--- 
+++ 
@@ -1,3 +1,29 @@
-At Sage days 30, a long brainstorm seems to have finalized the design. I'm writing a patch on sage combinat queue.
+At Sage days 30, a long brainstorm seems to have finalized the design. Here is a exerpt from the documentation:

-  
+A *set factory* `F` is device, whose goal is to construct parent `P`
+which models subsets of a big set `S`. Typically, the `P` s are constructed
+within families obtained by putting a bunch of constraints `cons` on the
+elements of the set `S`. In such a hierarchy of subsets, one needs to have a
+fine and easy control on the elements construction. That is, one often needs
+that `P` constructs elements in a subclass of its usual class for element. On
+the contrary, one also often needs `P` to be a facade parent, meaning that `P`
+construct element whose actual parent is not `P` itself.
+
+The role of a set factory is twofold:
+
+- *manage a database* of constructors for the different parents `P = F(cons)`
+  depending on the various kinds of constraints `cons`. Note: currently there
+  is no real support for that. We are gathering use case before fixing the
+  interface.
+
+- ensure that the elements `e = P(...)` created by the different parents
+  follows a consistent policy concerning their *class and parent*.
+
+The patch implement this idea while trying to leave as much as possible space 
+for further improvement. In particular, I tried to specify the few possible 
+things about constraints. I'm even not completely sure about `add_constraints`.
+Please comment and review.
+
+Florent
+
+**Apply :** [trac_10194-factories_policy-fh.patch](https://github.com/sagemath/sage-prod/files/10651310/trac_10194-factories_policy-fh.patch.gz)

[11d1fc49-71a1-44e1-869f-76be013245a0]

Work Issues: doctest failures

[11d1fc49-71a1-44e1-869f-76be013245a0]

comment:7

Attachment: trac_10194-factories_policy-fh.patch.gz

This fails doctests on every version tested -- see patchbot logs

[hivert]

comment:8

Replying to @loefflerd:

This fails doctests on every version tested -- see patchbot logs

I forgot a dependency to #10963. Thanks for pointing this out.

[hivert]

Dependencies: #10963

[11d1fc49-71a1-44e1-869f-76be013245a0]

comment:9

There is no patch at #10963. I don't think this can be meaningfully tagged as "needs review" when one of its dependencies doesn't exist yet.

[hivert]

comment:10

Replying to @loefflerd:

There is no patch at #10963. I don't think this can be meaningfully tagged as "needs review" when one of its dependencies doesn't exist yet.

As you can see on #10963, the patch is far for being inexistent as Simon and Christian started to review it. Of course it is on the Sage-Combinat queue. I need to ping Nicolas to have him finish it. Now, I don't see why having Nicolas's patch unfinished forbid me to have some feedback on this one. And asking for such a feedback seems to be a perfectly meaningful reason for putting "needs review"... The only reason I can see for not doing it is that it can trouble the patchbot. Do you have another one ?

[nthiery]

comment:11

Salut Florent!

Why is there a dependency on 10963? In the queue, this patch is much lower than 10963.

[nthiery]

comment:12

Ah, I see, it's about the glitch Sets().Facade() <-> Sets().Facades().

Since anyway the patch is up the queue, I suggest we finish commuting the two patches. Just use Sets().Facades() (we will need to keep the backward compatibility anyway).

With that, the tests pass up to to trivially failing doctests:

File "/opt/sage-5.0.beta11/devel/sage-combinat/sage/structureset_factories.py", line 644:
    sage: P2.category()
Expected:
    Join of Category of facade finite enumerated sets and Policy category with facade parent AllPairs
Got:
    Join of Category of finite enumerated sets and Policy category with facade parent AllPairs
**********************************************************************
File "/opt/sage-5.0.beta11/devel/sage-combinat/sage/structure/set_factories.py", line 972:
    sage: P.category()
Expected:
    Join of Category of facade finite enumerated sets and Policy category with facade parent AllPairs
Got:
    Join of Category of finite enumerated sets and Policy category with facade parent AllPairs

Cheers,

[fchapoton]

comment:14

Attachment: trac_10194-factories_policy-fh-v2.patch.gz

new version, rebased on 5.12.beta0, with cleanup

[fchapoton]

comment:15

I have made a git branch, but it seems to be massively broken.

Some problems come from Sets().Facade() versus Sets().Facades() as explained before

Some other problems come from #14519

And some other problems I do not understand..

---

New commits:

5dbd72b

trac_10194-factories_policy-fh.patch

[fchapoton]

Branch: u/chapoton/10194

[fchapoton]

Commit: 5dbd72b

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

57f3ed3

trac #10194 minor changes

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 5dbd72b to 57f3ed3

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 57f3ed3 to 28c42cb

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

28c42cb

trac #10194 typo corrections

[fchapoton]

comment:18

Temporary : emptied dependency field (was #10963)

[fchapoton]

Changed dependencies from #10963 to none

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 28c42cb to 6fa45d8

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

6fa45d8

trac #10194 other details, still not working :(

[fchapoton]

comment:20

This needs to be worked upon, as it is not working at all.

[fchapoton]

comment:21

Maybe some of the problems come from #13801 ?

[hivert]

Changed branch from u/chapoton/10194 to u/hivert/10194

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

06beedc

Fixed passing parent to ElementWrapper

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 6fa45d8 to 06beedc

[0f5ae6f6-e03a-45d9-b571-4ce01615e676]

Changed keywords from factories, days30, Cernay2012 to factories, days30, Cernay2012, days57

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

d7eb4c1

Cleanup in constraints managment.

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 06beedc to d7eb4c1

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

b615150

Fixed printing of `_repr_` for TopMostParentPolicy

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from d7eb4c1 to b615150

[fchapoton]

comment:29

Maybe you should add #13580 as a dependency ?

[hivert]

comment:30

Replying to @fchapoton:

Maybe you should add #13580 as a dependency ?

Why ? Those are completely different things.

[fchapoton]

comment:31

Then why do you have that in the commits of this ticket ?

[hivert]

comment:32

Replying to @fchapoton:

Then why do you have that in the commits of this ticket ?

I probably screwed things up with git ! I'm trying to fix the problem.

[0f5ae6f6-e03a-45d9-b571-4ce01615e676]

comment:33

For information, this features is largely tested in #16094

[hivert]

Changed branch from u/hivert/10194 to u/hivert/10194-rebased

[hivert]

Changed commit from b615150 to fc6981b

[hivert]

comment:35

Should be fixed now ! But I had to rebase the branch. So Nicolas, you will have to rebase yours at some point. Sorry !

---

New commits:

dc5dfc8	# Mon Apr 07 00:47:29 2014 +0200
e595280	Fixed passing parent to ElementWrapper
80b08c3	Cleanup in constraints managment.
fc6981b	Fixed printing of `_repr_` for TopMostParentPolicy

[hivert]

Changed branch from u/hivert/10194-rebased to u/hivert/10194-rebased-beta7

[0f5ae6f6-e03a-45d9-b571-4ce01615e676]

Changed branch from u/hivert/10194-rebased-beta7 to u/nborie/10194-rebased-beta7

[fchapoton]

Changed commit from fc6981b to 0eeecd1

[fchapoton]

comment:38

I have made one more commit. Now all tests pass, and code is in the pep8 standard.

---

New commits:

77279f9	# Mon Apr 07 00:47:29 2014 +0200
272d17f	Fixed passing parent to ElementWrapper
1491bff	Cleanup in constraints managment.
41c137e	Fixed printing of `_repr_` for TopMostParentPolicy
f76e0e6	Review : fonctionality, documentations, tests (very small things remains...)
1f3e02b	Merge branch 'u/nborie/10194-rebased-beta7' of trac.sagemath.org:sage into 10194
0eeecd1	trac #10194 make sure that all test pass (and pyflakes and pep8 compliant)

[fchapoton]

Changed branch from u/nborie/10194-rebased-beta7 to public/ticket/10194

[fchapoton]

comment:39

There remains a pyflakes warning thta needs to be taken care of :

src/sage/structure/set_factories.py:722: undefined name 'FacadeParentPolicyCategory'

[fchapoton]

Changed work issues from doctest failures to pyflakes warning