.. _cpp-allocator/shared_ptr:

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shared_ptr.hpp
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Full path: allocator/shared_ptr.hpp

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

.. cpp:namespace:: perm_group

.. class:: template<typename Perm> \
           shared_ptr_allocator

    An `Allocator` using reference-counting to guarantee no memory leaks,
    even when `release` is not used correctly.

    .. type:: perm = Perm
    .. type:: pointer = std::shared_ptr<perm>
    .. type:: const_pointer = std::shared_ptr<const perm>
    .. function:: explicit shared_ptr_allocator(std::size_t n)

        Construct an allocator that allocates permutations of degree `n`.
    .. function:: std::size_t degree() const
    .. function:: pointer make()

        :returns: `std::make_shared<perm>(perm_group::make_perm<perm>(degree()))`
    .. function:: pointer make_identity()

        :returns: `std::make_shared<perm>(perm_group::make_identity_perm<perm>(degree()))`
    .. function:: template<typename UPerm> pointer copy(UPerm &&p)

        :returns: `std::make_shared<perm>(perm_group::copy_perm<perm>(std::forward<UPerm>(p)))`
    .. function:: void release(const_pointer p)

        Does nothing, though at this stage `p` should be the sole reference to the permutation.