After the usual and well-known warning
General::compat: "Combinatorica Graph and Permutations functionality has been superseded
by preloaded functionality..."
that was present in version 10, a new warning appears:
SetDelayed::write: "Tag Element in a_List \[Element] {index___} is Protected."
This seems to be potentially serious.
Which statement in Combinatorica
causes it, and what are the consequences?
Edit 2016/09/10: Found it.
Combinatorica
contains a function Element
:
Element[a_List, {index___}] := a[[index]]
The function Element
in the environment System`
has the following added Information
:
Element[patt, dom] asserts that any expression matching the pattern patt is an element of dom. The use of the function Element in Combinatorica is now obsolete, though the function call Element[a, p] still gives the pth element of nested list a, where p is a list of indices.
So why do some users not get the warning/error but I do?
Unprotect
the symbolElement
, yet something either prevents this or restores the protected status. I suspect an interaction with auto-completion in the front end and setting the usage message onElement
. $\endgroup$