deprecate is_GapElement

[dimpase]

Removing the last uses of is_GapElement, deprecating it

Depends on #34770

CC: @mkoeppe

Component: interfaces

Author: Dima Pasechnik

Branch/Commit: e99db3a

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/34823

[dimpase]

Author: Dima Pasechnik

[dimpase]

Description changed:

--- 
+++ 
@@ -1 +1 @@
-
+Removing the last uses of `is_GapElement`, deprecating it

[dimpase]

Commit: 7c67a10

[dimpase]

Branch: u/dimpase/rings/remove_last_is_GapElement

[dimpase]

New commits:

21e38a7	fix coersion of libgap FFelements; switch to libgap
d4bde80	make imports of is_GapEelment uniform across files
eb72ef0	avoid is_GapElement
1c4a69f	use GapElement from an abstract superclass
6e5ea79	move import of libgap into a function
adc231e	remove is_GapElement from number fields code
7c67a10	deprecating is_GapElement

[dimpase]

comment:3

sage/rings/ still need work to convert to libgap, it's not done here.

[mkoeppe]

comment:4

 def is_GapElement(x):
     """
+    Deprecated function
+
+    Use isinstance(x,GapElement)
+
     Returns True if x is a GapElement.
 
     EXAMPLES::
 
         sage: from sage.interfaces.gap import is_GapElement
         sage: is_GapElement(gap(2))
+        doctest:...: DeprecationWarning: The function is_GapElement is deprecated. Use isinstance(x, GapElement) instead
+        See https://trac.sagemath.org/34823 for details.

This needs better rst markup. Also, I think the message should point to sage.interfaces.abc specifically

[sagetrac-git]

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

6c75e9b

better rst, point at sage.interfaces.abc to use

[sagetrac-git]

Changed commit from 7c67a10 to 6c75e9b

[dimpase]

comment:6

OK, done