Code quality: Possibility to declare some outparams as reference to const in some header files?

[krishnakumarg1984]

In proximal.h, static analysis flags that out can be declared as a reference to const.

  void operator()(Vector<T> &out, typename real_type<T>::type, Vector<T> const &x) const {
    return operator()(out, x);
  }

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In relative_variation.h,

  RelativeVariation &tolerance(Real &e) const {
    tolerance_ = e;
    return *this;
  }

Parameter e can be declared as reference to const.

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Any thoughts on these?