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/**
* @file aka_common.hh
*
* @author Guillaume Anciaux <guillaume.anciaux@epfl.ch>
* @author Nicolas Richart <nicolas.richart@epfl.ch>
*
* @date creation: Mon Jun 14 2010
* @date last modification: Sat May 01 2021
*
* @brief common type descriptions for akantu
*
*
* @section LICENSE
*
* Copyright (©) 2010-2021 EPFL (Ecole Polytechnique Fédérale de Lausanne)
* Laboratory (LSMS - Laboratoire de Simulation en Mécanique des Solides)
*
* Akantu is free software: you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License as published by the Free
* Software Foundation, either version 3 of the License, or (at your option) any
* later version.
*
* Akantu is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
* A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Akantu. If not, see <http://www.gnu.org/licenses/>.
*
*/
/* -------------------------------------------------------------------------- */
#ifndef AKANTU_COMMON_HH_
#define AKANTU_COMMON_HH_
#include "aka_compatibilty_with_cpp_standard.hh"
/* -------------------------------------------------------------------------- */
#if defined(WIN32)
#define __attribute__(x)
#endif
/* -------------------------------------------------------------------------- */
#include "aka_config.hh"
#include "aka_error.hh"
#include "aka_safe_enum.hh"
/* -------------------------------------------------------------------------- */
#include <boost/preprocessor.hpp>
#include <limits>
#include <list>
#include <memory>
#include <string>
#include <type_traits>
#include <unordered_map>
/* -------------------------------------------------------------------------- */
namespace akantu {
/* -------------------------------------------------------------------------- */
/* Constants */
/* -------------------------------------------------------------------------- */
namespace {
[[gnu::unused]] constexpr Int _all_dimensions{
std::numeric_limits<UInt>::max()};
#ifdef AKANTU_NDEBUG
[[gnu::unused]] constexpr Real REAL_INIT_VALUE{0.};
#else
[[gnu::unused]] constexpr Real REAL_INIT_VALUE{
std::numeric_limits<Real>::quiet_NaN()};
#endif
} // namespace
/* -------------------------------------------------------------------------- */
/* Common types */
/* -------------------------------------------------------------------------- */
using ID = std::string;
} // namespace akantu
/* -------------------------------------------------------------------------- */
#include "aka_enum_macros.hh"
/* -------------------------------------------------------------------------- */
#include "aka_element_classes_info.hh"
/* -------------------------------------------------------------------------- */
namespace akantu {
/* -------------------------------------------------------------------------- */
/* Mesh/FEM/Model types */
/* -------------------------------------------------------------------------- */
/// small help to use names for directions
enum SpatialDirection { _x = 0, _y = 1, _z = 2 };
/// enum MeshIOType type of mesh reader/writer
enum MeshIOType {
_miot_auto, ///< Auto guess of the reader to use based on the extension
_miot_gmsh, ///< Gmsh files
_miot_gmsh_struct, ///< Gsmh reader with reintpretation of elements has
/// structures elements
_miot_diana, ///< TNO Diana mesh format
_miot_abaqus ///< Abaqus mesh format
};
/// enum MeshEventHandlerPriority defines relative order of execution of
/// events
enum EventHandlerPriority {
_ehp_highest = 0,
_ehp_mesh = 5,
_ehp_fe_engine = 9,
_ehp_synchronizer = 10,
_ehp_dof_manager = 20,
_ehp_model = 94,
_ehp_non_local_manager = 100,
_ehp_lowest = 100
};
#if !defined(DOXYGEN)
// clang-format off
#define AKANTU_MODEL_TYPES \
(model) \
(solid_mechanics_model) \
(solid_mechanics_model_cohesive) \
(heat_transfer_model) \
(structural_mechanics_model) \
(embedded_model) \
(contact_mechanics_model) \
(coupler_solid_contact) \
(coupler_solid_cohesive_contact) \
(phase_field_model) \
(coupler_solid_phasefield)
// clang-format on
/// enum ModelType defines which type of physics is solved
AKANTU_CLASS_ENUM_DECLARE(ModelType, AKANTU_MODEL_TYPES)
AKANTU_CLASS_ENUM_OUTPUT_STREAM(ModelType, AKANTU_MODEL_TYPES)
AKANTU_CLASS_ENUM_INPUT_STREAM(ModelType, AKANTU_MODEL_TYPES)
#else
enum class ModelType {
model,
solid_mechanics_model,
solid_mechanics_model_cohesive,
heat_transfer_model,
structural_mechanics_model,
embedded_model,
};
#endif
/// enum AnalysisMethod type of solving method used to solve the equation of
/// motion
enum AnalysisMethod {
_static = 0,
_implicit_dynamic = 1,
_explicit_lumped_mass = 2,
_explicit_lumped_capacity = 2,
_explicit_consistent_mass = 3,
_explicit_contact = 4,
_implicit_contact = 5
};
/// enum DOFSupportType defines which kind of dof that can exists
enum DOFSupportType { _dst_nodal, _dst_generic };
#if !defined(DOXYGEN)
// clang-format off
#define AKANTU_NON_LINEAR_SOLVER_TYPES \
(linear) \
(newton_raphson) \
(newton_raphson_modified) \
(lumped) \
(gmres) \
(bfgs) \
(cg) \
(newton_raphson_contact) \
(auto)
// clang-format on
AKANTU_CLASS_ENUM_DECLARE(NonLinearSolverType, AKANTU_NON_LINEAR_SOLVER_TYPES)
AKANTU_CLASS_ENUM_OUTPUT_STREAM(NonLinearSolverType,
AKANTU_NON_LINEAR_SOLVER_TYPES)
AKANTU_CLASS_ENUM_INPUT_STREAM(NonLinearSolverType,
AKANTU_NON_LINEAR_SOLVER_TYPES)
#else
/// Type of non linear resolution available in akantu
enum class NonLinearSolverType {
_linear, ///< No non linear convergence loop
_newton_raphson, ///< Regular Newton-Raphson
_newton_raphson_modified, ///< Newton-Raphson with initial tangent
_lumped, ///< Case of lumped mass or equivalent matrix
_gmres,
_bfgs,
_cg,
_newton_raphson_contact, ///< Regular Newton-Raphson modified
/// for contact problem
_auto, ///< This will take a default value that make sense in case of
/// model::getNewSolver
};
#endif
#if !defined(DOXYGEN)
// clang-format off
#define AKANTU_TIME_STEP_SOLVER_TYPE \
(static) \
(dynamic) \
(dynamic_lumped) \
(not_defined)
// clang-format on
AKANTU_CLASS_ENUM_DECLARE(TimeStepSolverType, AKANTU_TIME_STEP_SOLVER_TYPE)
AKANTU_CLASS_ENUM_OUTPUT_STREAM(TimeStepSolverType,
AKANTU_TIME_STEP_SOLVER_TYPE)
AKANTU_CLASS_ENUM_INPUT_STREAM(TimeStepSolverType, AKANTU_TIME_STEP_SOLVER_TYPE)
#else
/// Type of time stepping solver
enum class TimeStepSolverType {
_static, ///< Static solution
_dynamic, ///< Dynamic solver
_dynamic_lumped, ///< Dynamic solver with lumped mass
_not_defined, ///< For not defined cases
};
#endif
#if !defined(DOXYGEN)
// clang-format off
#define AKANTU_INTEGRATION_SCHEME_TYPE \
(pseudo_time) \
(forward_euler) \
(trapezoidal_rule_1) \
(backward_euler) \
(central_difference) \
(fox_goodwin) \
(trapezoidal_rule_2) \
(linear_acceleration) \
(newmark_beta) \
(generalized_trapezoidal)
// clang-format on
AKANTU_CLASS_ENUM_DECLARE(IntegrationSchemeType, AKANTU_INTEGRATION_SCHEME_TYPE)
AKANTU_CLASS_ENUM_OUTPUT_STREAM(IntegrationSchemeType,
AKANTU_INTEGRATION_SCHEME_TYPE)
AKANTU_CLASS_ENUM_INPUT_STREAM(IntegrationSchemeType,
AKANTU_INTEGRATION_SCHEME_TYPE)
#else
/// Type of integration scheme
enum class IntegrationSchemeType {
_pseudo_time, ///< Pseudo Time
_forward_euler, ///< GeneralizedTrapezoidal(0)
_trapezoidal_rule_1, ///< GeneralizedTrapezoidal(1/2)
_backward_euler, ///< GeneralizedTrapezoidal(1)
_central_difference, ///< NewmarkBeta(0, 1/2)
_fox_goodwin, ///< NewmarkBeta(1/6, 1/2)
_trapezoidal_rule_2, ///< NewmarkBeta(1/2, 1/2)
_linear_acceleration, ///< NewmarkBeta(1/3, 1/2)
_newmark_beta, ///< generic NewmarkBeta with user defined
/// alpha and beta
_generalized_trapezoidal ///< generic GeneralizedTrapezoidal with user
/// defined alpha
};
#endif
#if !defined(DOXYGEN)
// clang-format off
#define AKANTU_SOLVE_CONVERGENCE_CRITERIA \
(residual) \
(solution) \
(residual_mass_wgh)
// clang-format on
AKANTU_CLASS_ENUM_DECLARE(SolveConvergenceCriteria,
AKANTU_SOLVE_CONVERGENCE_CRITERIA)
AKANTU_CLASS_ENUM_OUTPUT_STREAM(SolveConvergenceCriteria,
AKANTU_SOLVE_CONVERGENCE_CRITERIA)
AKANTU_CLASS_ENUM_INPUT_STREAM(SolveConvergenceCriteria,
AKANTU_SOLVE_CONVERGENCE_CRITERIA)
#else
/// enum SolveConvergenceCriteria different convergence criteria
enum class SolveConvergenceCriteria {
_residual, ///< Use residual to test the convergence
_solution, ///< Use solution to test the convergence
_residual_mass_wgh ///< Use residual weighted by inv. nodal mass to
///< testb
};
#endif
/// enum CohesiveMethod type of insertion of cohesive elements
enum CohesiveMethod { _intrinsic, _extrinsic };
/// @enum MatrixType type of sparse matrix used
enum MatrixType { _unsymmetric, _symmetric, _mt_not_defined };
/// @enum Type of contact detection
enum DetectionType { _explicit, _implicit };
#if !defined(DOXYGEN)
// clang-format off
#define AKANTU_CONTACT_STATE \
(no_contact) \
(stick) \
(slip)
// clang-format on
AKANTU_CLASS_ENUM_DECLARE(ContactState,
AKANTU_CONTACT_STATE)
AKANTU_CLASS_ENUM_OUTPUT_STREAM(ContactState,
AKANTU_CONTACT_STATE)
AKANTU_CLASS_ENUM_INPUT_STREAM(ContactState,
AKANTU_CONTACT_STATE)
#else
/// @enum no contact or stick or slip state
enum class ContactState {
_no_contact = 0,
_stick = 1,
_slip = 2,
};
#endif
/* -------------------------------------------------------------------------- */
/* Ghosts handling */
/* -------------------------------------------------------------------------- */
/// @enum CommunicatorType type of communication method to use
enum CommunicatorType { _communicator_mpi, _communicator_dummy };
#if !defined(DOXYGEN)
// clang-format off
#define AKANTU_SYNCHRONIZATION_TAG \
(whatever) \
(update) \
(ask_nodes) \
(size) \
(smm_mass) \
(smm_for_gradu) \
(smm_boundary) \
(smm_uv) \
(smm_res) \
(smm_init_mat) \
(smm_stress) \
(smmc_facets) \
(smmc_facets_conn) \
(smmc_facets_stress) \
(smmc_damage) \
(giu_global_conn) \
(ce_groups) \
(ce_insertion_order) \
(gm_clusters) \
(htm_temperature) \
(htm_gradient_temperature) \
(htm_phi) \
(htm_gradient_phi) \
(pfm_damage) \
(pfm_driving) \
(pfm_history) \
(pfm_energy) \
(csp_damage) \
(csp_strain) \
(mnl_for_average) \
(mnl_weight) \
(nh_criterion) \
(test) \
(user_1) \
(user_2) \
(material_id) \
(for_dump) \
(cf_nodal) \
(cf_incr) \
(solver_solution)
// clang-format on
AKANTU_CLASS_ENUM_DECLARE(SynchronizationTag, AKANTU_SYNCHRONIZATION_TAG)
AKANTU_CLASS_ENUM_OUTPUT_STREAM(SynchronizationTag, AKANTU_SYNCHRONIZATION_TAG)
#else
/// @enum SynchronizationTag type of synchronizations
enum class SynchronizationTag {
//--- Generic tags ---
_whatever,
_update,
_ask_nodes,
_size,
//--- SolidMechanicsModel tags ---
_smm_mass, ///< synchronization of the SolidMechanicsModel.mass
_smm_for_gradu, ///< synchronization of the
/// SolidMechanicsModel.displacement
_smm_boundary, ///< synchronization of the boundary, forces, velocities
/// and displacement
_smm_uv, ///< synchronization of the nodal velocities and displacement
_smm_res, ///< synchronization of the nodal residual
_smm_init_mat, ///< synchronization of the data to initialize materials
_smm_stress, ///< synchronization of the stresses to compute the
///< internal
/// forces
_smmc_facets, ///< synchronization of facet data to setup facet synch
_smmc_facets_conn, ///< synchronization of facet global connectivity
_smmc_facets_stress, ///< synchronization of facets' stress to setup
///< facet
/// synch
_smmc_damage, ///< synchronization of damage
// --- GlobalIdsUpdater tags ---
_giu_global_conn, ///< synchronization of global connectivities
// --- CohesiveElementInserter tags ---
_ce_groups, ///< synchronization of cohesive element insertion depending
/// on facet groups
_ce_insertion_order, ///< synchronization of the order of insertion of
/// cohesive elements
// --- GroupManager tags ---
_gm_clusters, ///< synchronization of clusters
// --- HeatTransfer tags ---
_htm_temperature, ///< synchronization of the nodal temperature
_htm_gradient_temperature, ///< synchronization of the element gradient
/// temperature
// --- PhaseFieldModel tags ---
_pfm_damage, ///< synchronization of the nodal damage
_pfm_driving, ///< synchronization of the driving forces to
/// compute the internal
_pfm_history, ///< synchronization of the damage history to
/// compute the internal
_pfm_energy, ///< synchronization of the damage energy
/// density to compute the internal
// --- CouplerSolidPhaseField tags ---
_csp_damage, ///< synchronization of the damage from phase
/// model to solid model
_csp_strain, ///< synchronization of the strain from solid
/// model to phase model
// --- LevelSet tags ---
_htm_phi, ///< synchronization of the nodal level set value phi
_htm_gradient_phi, ///< synchronization of the element gradient phi
//--- Material non local ---
_mnl_for_average, ///< synchronization of data to average in non local
/// material
_mnl_weight, ///< synchronization of data for the weight computations
// --- NeighborhoodSynchronization tags ---
_nh_criterion,
// --- General tags ---
_test, ///< Test tag
_user_1, ///< tag for user simulations
_user_2, ///< tag for user simulations
_material_id, ///< synchronization of the material ids
_for_dump, ///< everything that needs to be synch before dump
// --- Contact & Friction ---
_cf_nodal, ///< synchronization of disp, velo, and current position
_cf_incr, ///< synchronization of increment
// --- Solver tags ---
_solver_solution ///< synchronization of the solution obained with the
/// PETSc solver
};
#endif
/// @enum GhostType type of ghost
enum GhostType {
_not_ghost = 0,
_ghost = 1,
_casper // not used but a real cute ghost
};
/// Define the flag that can be set to a node
enum class NodeFlag : std::uint8_t {
_normal = 0x00,
_distributed = 0x01,
_master = 0x03,
_slave = 0x05,
_pure_ghost = 0x09,
_shared_mask = 0x0F,
_periodic = 0x10,
_periodic_master = 0x30,
_periodic_slave = 0x50,
_periodic_mask = 0xF0,
_local_master_mask = 0xCC, // ~(_master & _periodic_mask)
};
inline NodeFlag operator&(const NodeFlag & a, const NodeFlag & b) {
using under = std::underlying_type_t<NodeFlag>;
return NodeFlag(under(a) & under(b));
}
inline NodeFlag operator|(const NodeFlag & a, const NodeFlag & b) {
using under = std::underlying_type_t<NodeFlag>;
return NodeFlag(under(a) | under(b));
}
inline NodeFlag & operator|=(NodeFlag & a, const NodeFlag & b) {
a = a | b;
return a;
}
inline NodeFlag & operator&=(NodeFlag & a, const NodeFlag & b) {
a = a & b;
return a;
}
inline NodeFlag operator~(const NodeFlag & a) {
using under = std::underlying_type_t<NodeFlag>;
return NodeFlag(~under(a));
}
std::ostream & operator<<(std::ostream & stream, NodeFlag flag);
} // namespace akantu
AKANTU_ENUM_HASH(GhostType)
namespace akantu {
/* -------------------------------------------------------------------------- */
struct GhostType_def {
using type = GhostType;
static const type _begin_ = _not_ghost;
static const type _end_ = _casper;
};
using ghost_type_t = safe_enum<GhostType_def>;
namespace {
constexpr ghost_type_t ghost_types{_casper};
}
/// standard output stream operator for GhostType
// inline std::ostream & operator<<(std::ostream & stream, GhostType type);
/* -------------------------------------------------------------------------- */
/* Global defines */
/* -------------------------------------------------------------------------- */
#define AKANTU_MIN_ALLOCATION 2000
#define AKANTU_INDENT ' '
#define AKANTU_INCLUDE_INLINE_IMPL
/* -------------------------------------------------------------------------- */
#define AKANTU_SET_MACRO(name, variable, type) \
inline void set##name(type variable) { this->variable = variable; }
#define AKANTU_GET_MACRO(name, variable, type) \
inline auto get##name() const->type { return variable; }
#define AKANTU_GET_MACRO_AUTO(name, variable) \
inline decltype(auto) get##name() const { return (variable); }
#define AKANTU_GET_MACRO_AUTO_NOT_CONST(name, variable) \
inline decltype(auto) get##name() { return (variable); }
#define AKANTU_GET_MACRO_NOT_CONST(name, variable, type) \
inline auto get##name()->type { return variable; }
#define AKANTU_GET_MACRO_DEREF_PTR(name, ptr) \
inline const auto & get##name() const { \
if (not(ptr)) { \
AKANTU_EXCEPTION("The member " << #ptr << " is not initialized"); \
} \
return (*(ptr)); \
}
#define AKANTU_GET_MACRO_DEREF_PTR_NOT_CONST(name, ptr) \
inline auto & get##name() { \
if (not(ptr)) { \
AKANTU_EXCEPTION("The member " << #ptr << " is not initialized"); \
} \
return (*(ptr)); \
}
#define AKANTU_GET_MACRO_DEREF_PTR_NOT_CONST(name, ptr) \
inline decltype(auto) get##name() { \
if (not ptr) { \
AKANTU_EXCEPTION("The member " << #ptr << " is not initialized"); \
} \
return (*ptr); \
}
#define AKANTU_GET_MACRO_BY_SUPPORT_TYPE(name, variable, type, support, con) \
inline auto get##name(const support & el_type, \
GhostType ghost_type = _not_ghost) \
con -> con Array<type> & { \
return variable(el_type, ghost_type); \
} // NOLINT
#define AKANTU_GET_MACRO_BY_ELEMENT_TYPE(name, variable, type) \
AKANTU_GET_MACRO_BY_SUPPORT_TYPE(name, variable, type, ElementType, )
#define AKANTU_GET_MACRO_BY_ELEMENT_TYPE_CONST(name, variable, type) \
AKANTU_GET_MACRO_BY_SUPPORT_TYPE(name, variable, type, ElementType, const)
#define AKANTU_GET_MACRO_BY_GEOMETRIE_TYPE(name, variable, type) \
AKANTU_GET_MACRO_BY_SUPPORT_TYPE(name, variable, type, GeometricalType, )
#define AKANTU_GET_MACRO_BY_GEOMETRIE_TYPE_CONST(name, variable, type) \
AKANTU_GET_MACRO_BY_SUPPORT_TYPE(name, variable, type, GeometricalType, const)
/* -------------------------------------------------------------------------- */
/// initialize the static part of akantu
void initialize(int & argc, char **& argv);
/// initialize the static part of akantu and read the global input_file
void initialize(const std::string & input_file, int & argc, char **& argv);
/* -------------------------------------------------------------------------- */
/// finilize correctly akantu and clean the memory
void finalize();
/* -------------------------------------------------------------------------- */
/// Read an new input file
void readInputFile(const std::string & input_file);
/* -------------------------------------------------------------------------- */
/* -------------------------------------------------------------------------- */
/* string manipulation */
/* -------------------------------------------------------------------------- */
inline auto to_lower(const std::string & str) -> std::string;
/* -------------------------------------------------------------------------- */
inline auto trim(const std::string & to_trim) -> std::string;
inline auto trim(const std::string & to_trim, char c) -> std::string;
/* -------------------------------------------------------------------------- */
/* -------------------------------------------------------------------------- */
/// give a string representation of the a human readable size in bit
template <typename T> auto printMemorySize(UInt size) -> std::string;
/* -------------------------------------------------------------------------- */
struct TensorTrait {};
struct TensorProxyTrait {};
} // namespace akantu
/* -------------------------------------------------------------------------- */
/* Type traits */
/* -------------------------------------------------------------------------- */
namespace aka {
/* ------------------------------------------------------------------------ */
template <typename T> using is_scalar = std::is_arithmetic<T>;
/* ------------------------------------------------------------------------ */
template <typename R, typename T,
std::enable_if_t<std::is_reference<T>::value> * = nullptr>
auto is_of_type(T && t) -> bool {
return (
dynamic_cast<std::add_pointer_t<
std::conditional_t<std::is_const<std::remove_reference_t<T>>::value,
std::add_const_t<R>, R>>>(&t) != nullptr);
}
/* -------------------------------------------------------------------------- */
template <typename R, typename T>
auto is_of_type(std::unique_ptr<T> & t) -> bool {
return (
dynamic_cast<std::add_pointer_t<
std::conditional_t<std::is_const<T>::value, std::add_const_t<R>, R>>>(
t.get()) != nullptr);
}
/* ------------------------------------------------------------------------ */
template <typename R, typename T,
std::enable_if_t<std::is_reference<T>::value> * = nullptr>
decltype(auto) as_type(T && t) {
static_assert(
disjunction<
std::is_base_of<std::decay_t<T>, std::decay_t<R>>, // down-cast
std::is_base_of<std::decay_t<R>, std::decay_t<T>> // up-cast
>::value,
"Type T and R are not valid for a as_type conversion");
return dynamic_cast<std::add_lvalue_reference_t<
std::conditional_t<std::is_const<std::remove_reference_t<T>>::value,
std::add_const_t<R>, R>>>(t);
}
/* -------------------------------------------------------------------------- */
template <typename R, typename T,
std::enable_if_t<std::is_pointer<T>::value> * = nullptr>
decltype(auto) as_type(T && t) {
return &as_type<R>(*t);
}
/* -------------------------------------------------------------------------- */
template <typename R, typename T>
decltype(auto) as_type(const std::shared_ptr<T> & t) {
return std::dynamic_pointer_cast<R>(t);
}
} // namespace aka
#include "aka_common_inline_impl.hh"
#include "aka_fwd.hh"
namespace akantu {
/// get access to the internal argument parser
cppargparse::ArgumentParser & getStaticArgumentParser();
/// get access to the internal input file parser
Parser & getStaticParser();
/// get access to the user part of the internal input file parser
const ParserSection & getUserParser();
#define AKANTU_CURRENT_FUNCTION \
(std::string(__func__) + "():" + std::to_string(__LINE__))
} // namespace akantu
/* -------------------------------------------------------------------------- */
#if AKANTU_INTEGER_SIZE == 4
#define AKANTU_HASH_COMBINE_MAGIC_NUMBER 0x9e3779b9
#elif AKANTU_INTEGER_SIZE == 8
#define AKANTU_HASH_COMBINE_MAGIC_NUMBER 0x9e3779b97f4a7c13LL
#endif
namespace std {
/**
* Hashing function for pairs based on hash_combine from boost The magic
* number is coming from the golden number @f[\phi = \frac{1 + \sqrt5}{2}@f]
* @f[\frac{2^32}{\phi} = 0x9e3779b9@f]
* http://stackoverflow.com/questions/4948780/magic-number-in-boosthash-combine
* http://burtleburtle.net/bob/hash/doobs.html
*/
template <typename a, typename b> struct hash<std::pair<a, b>> {
hash() = default;
auto operator()(const std::pair<a, b> & p) const -> std::size_t {
size_t seed = ah(p.first);
return bh(p.second) + AKANTU_HASH_COMBINE_MAGIC_NUMBER + (seed << 6) +
(seed >> 2);
}
private:
const hash<a> ah{};
const hash<b> bh{};
};
} // namespace std
#endif // AKANTU_COMMON_HH_
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