[PATCH] Remove redundant accessors in hash tables

[François Dumont]

On 5/15/19 5:37 PM, Jonathan Wakely wrote:
> François,
> I noticed that _Hash_code_base and _Hashtable_base have a number of
> member functions which are overloaded for const and non-const:
>
> Â Â  const _Equal&
> Â Â  _M_eq() const { return _EqualEBO::_S_cget(*this); }
>
> Â Â  _Equal&
> Â Â  _M_eq() { return _EqualEBO::_S_get(*this); }
>
> The non-const ones seem to be unnecessary. They're used in the _M_swap
> member functions, but all other uses could (and probably should) call
> the const overload to get a const reference to the function object.
>
> If we make the _M_swap members use the EBO accessors directly then we
> can get rid of the non-const accessors. That makes overload resolution
> simpler for the compiler (as there's only one function to choose from)
> and should result in slightly smaller code when inlining is not
> enabled.
>
> Do you see any problem with this patch?
>
>
I think it is more a Pavlov behavior, always providing const and 
non-const no matter what.

No problem to simplify this.