Link formatting
---------------

especially the hash "#" character is problematic for LaTeX as it is
used in LaTeX's macro language.

Contributed by d.abrahams

.. Sidebar:: ``const`` and an iterator's ``value_type``

   argument will be correct for all `lvalue iterators`_.

.. _`lvalue iterators`: new-iter-concepts.html#lvalue-iterators-lib-lvalue-iterators

