.. _cpp-aut/pruner_base:

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pruner_base.hpp
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Full path: ``graph_canon/aut/pruner_base.hpp``

.. default-domain:: cpp
.. default-role:: cpp:expr

.. cpp:namespace:: graph_canon

.. class:: template<typename Iter> aut_range

    An adaptor for pairs of iterators to be exposed as a range.

    .. function:: aut_range(Iter first, Iter last)
    .. function:: Iter begin() const
    .. function:: Iter end() const

.. function:: template<typename Iter> auto make_aut_range(Iter first, Iter last)

    :returns: `aut_range<Iter>(first, last)`


.. class:: template<typename Derived> \
           aut_pruner_base

    A base class for implementing visitors for automorphism pruning.

    :tparam Derived: The subclass of this class (that is, the CRTP pattern).

    For

    - a `canon_state` object `state`,
    - a `tree_node` object `t`,
    - a permutation `aut` representing an automorphism, and
    - the object `derived = static_cast<Derived&>(*this)`

    the following expressions must be valid:

    - | Expression: `derived.add_automorphism(state, t, aut)`
      | Semantics: store the new automorphism `aut`
    - | Expression: `derived.need_update(state, t)`
      | Returns: a boolean telling whether the node needs updating.
      | Notes: is only called on non-pruned, non-leaf nodes.
    - | Expression: `derived.update(state, t)`
      | Returns: a possibly empty range of automorphism generators (e.g., an `aut_range`) added to the stabilizer of `t` after updating it.