Add unset_cache() to remove single keys from a cached_method

[saraedum]

A cached_method's clear_cache() clears the entire dictionary of a cached_method. Currently, there is no way to only remove some keys. This is sometimes necessary if values in the cache are not usable anymore (e.g. because they are defined in some external expect interface but the external session is not running anymore).

Component: misc

Keywords: cached_method

Author: Julian Rueth

Branch/Commit: u/saraedum/ticket/16505 @ 9cee22e

Issue created by migration from https://trac.sagemath.org/ticket/16505

[saraedum]

Branch: u/saraedum/ticket/16505

[sagetrac-git]

Commit: 7b01ec8

[sagetrac-git]

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

7b01ec8

Merge branch 'develop' into ticket/16505

[sagetrac-git]

Changed commit from 7b01ec8 to 91e09ce

[sagetrac-git]

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

91e09ce

Merge branch 'develop' into ticket/16505

[nathanncohen]

comment:7

From the looks of the function set_cache just above the one that you define, it seems that you should also handle the case of non-hashable keys.

Nathann

[sagetrac-git]

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

01f8fce

Merge branch 'develop' into t/16505/ticket/16505

[sagetrac-git]

Changed commit from 91e09ce to 01f8fce

[sagetrac-git]

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

29d8e83

handle unhashable keys in unset_cache

[sagetrac-git]

Changed commit from 01f8fce to 29d8e83

[jdemeyer]

comment:10

Please rebase this on top of #19768.

[jdemeyer]

Dependencies: #19768

[jdemeyer]

Changed dependencies from #19768 to none

[sagetrac-git]

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

0bcb93f

Merge branch 'develop' into t/16505/ticket/16505

[sagetrac-git]

Changed commit from 29d8e83 to 0bcb93f

[sagetrac-git]

Changed commit from 0bcb93f to 9cee22e

[sagetrac-git]

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

9cee22e

fix build error

[jdemeyer]

comment:15

Please use the get_key_args_kwds() and dict_key() functions added recently to cached functions.

[jdemeyer]

Replying to @saraedum:

Currently, there is no way to only remove some keys. This is sometimes necessary if values in the cache are not usable anymore

For this use case, I see no reason to raise KeyError when the key does not exist: I would just ignore non-existing keys.

You should add doctests showing that this also works for a weak cached function and a cached method (not just plain cached functions).