Eigen/src/Core/util/ForwardDeclarations.h

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2007-2010 Benoit Jacob <jacob.benoit.1@gmail.com>
// Copyright (C) 2008-2009 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// SPDX-License-Identifier: MPL-2.0

#ifndef EIGEN_FORWARDDECLARATIONS_H
#define EIGEN_FORWARDDECLARATIONS_H

// IWYU pragma: private
#include "../InternalHeaderCheck.h"

namespace Eigen {
namespace internal {

template <typename T>
struct traits;

// here we say once and for all that traits<const T> == traits<T>
// When constness must affect traits, it has to be constness on template parameters on which T itself depends.
// For example, traits<Map<const T> > != traits<Map<T> >, but
//              traits<const Map<T> > == traits<Map<T> >
template <typename T>
struct traits<const T> : traits<T> {};

template <typename Derived>
struct has_direct_access : bool_constant<(traits<Derived>::Flags & DirectAccessBit) != 0> {};

template <typename Derived>
struct accessors_level {
  enum {
    has_direct_access = (traits<Derived>::Flags & DirectAccessBit) ? 1 : 0,
    has_write_access = (traits<Derived>::Flags & LvalueBit) ? 1 : 0,
    value = has_direct_access ? (has_write_access ? DirectWriteAccessors : DirectAccessors)
                              : (has_write_access ? WriteAccessors : ReadOnlyAccessors)
  };
};

template <typename T>
struct evaluator_traits;

template <typename T>
struct evaluator;

}  // end namespace internal

template <typename T>
struct NumTraits;

template <typename Derived>
struct EigenBase;
template <typename Derived>
class DenseBase;
template <typename Derived>
class PlainObjectBase;
template <typename Derived, int Level>
class DenseCoeffsBase;

template <typename Scalar_, int Rows_, int Cols_,
          int Options_ = AutoAlign | ((Rows_ == 1 && Cols_ != 1)   ? Eigen::RowMajor
                                      : (Cols_ == 1 && Rows_ != 1) ? Eigen::ColMajor
                                                                   : EIGEN_DEFAULT_MATRIX_STORAGE_ORDER_OPTION),
          int MaxRows_ = Rows_, int MaxCols_ = Cols_>
class Matrix;

template <typename Derived>
class MatrixBase;
template <typename Derived>
class ArrayBase;

template <typename ExpressionType, template <typename> class StorageBase>
class NoAlias;
template <typename ExpressionType>
class NestByValue;
template <typename ExpressionType>
class SwapWrapper;

template <typename XprType, int BlockRows = Dynamic, int BlockCols = Dynamic, bool InnerPanel = false>
class Block;
template <typename XprType, typename RowIndices, typename ColIndices>
class IndexedView;
template <typename XprType, int Rows = Dynamic, int Cols = Dynamic, int Order = 0>
class Reshaped;
template <typename FirstType, typename SizeType, typename IncrType>
class ArithmeticSequence;

template <typename MatrixType, int Size = Dynamic>
class VectorBlock;
template <typename MatrixType>
class Transpose;
template <typename MatrixType>
class Conjugate;
template <typename NullaryOp, typename MatrixType>
class CwiseNullaryOp;
template <typename UnaryOp, typename MatrixType>
class CwiseUnaryOp;
template <typename BinaryOp, typename Lhs, typename Rhs>
class CwiseBinaryOp;
template <typename TernaryOp, typename Arg1, typename Arg2, typename Arg3>
class CwiseTernaryOp;
template <typename Decomposition, typename Rhstype>
class Solve;
template <typename XprType>
class Inverse;

template <typename Lhs, typename Rhs, int Option = DefaultProduct>
class Product;

template <typename Derived>
class DiagonalBase;
template <typename DiagonalVectorType_>
class DiagonalWrapper;
template <typename Scalar_, int SizeAtCompileTime, int MaxSizeAtCompileTime = SizeAtCompileTime>
class DiagonalMatrix;
template <typename MatrixType, int Index = 0>
class Diagonal;
template <typename Derived>
class SkewSymmetricBase;
template <typename VectorType_>
class SkewSymmetricWrapper;
template <typename Scalar_>
class SkewSymmetricMatrix3;
template <int SizeAtCompileTime, int MaxSizeAtCompileTime = SizeAtCompileTime, typename IndexType = int>
class PermutationMatrix;
template <typename Scalar_, int SizeAtCompileTime, int MaxSizeAtCompileTime = SizeAtCompileTime,
          typename StorageIndex_ = int>
class ScaledPermutationMatrix;
template <typename Derived>
class ScaledPermutationBase;
template <int SizeAtCompileTime, int MaxSizeAtCompileTime = SizeAtCompileTime, typename IndexType = int>
class Transpositions;
template <typename Derived>
class PermutationBase;
template <typename Derived>
class TranspositionsBase;
template <typename IndicesType_>
class PermutationWrapper;
template <typename IndicesType_>
class TranspositionsWrapper;

template <typename Derived,
          int Level = internal::accessors_level<Derived>::has_write_access ? WriteAccessors : ReadOnlyAccessors>
class MapBase;
template <int OuterStrideAtCompileTime, int InnerStrideAtCompileTime>
class Stride;
template <int Value = Dynamic>
class InnerStride;
template <int Value = Dynamic>
class OuterStride;
template <typename MatrixType, int MapOptions = Unaligned, typename StrideType = Stride<0, 0>>
class Map;
template <typename Derived>
class RefBase;
template <typename PlainObjectType, int Options = 0,
          typename StrideType =
              std::conditional_t<PlainObjectType::IsVectorAtCompileTime, InnerStride<1>, OuterStride<>>>
class Ref;
template <typename ViewOp, typename MatrixType, typename StrideType = Stride<0, 0>>
class CwiseUnaryView;

template <typename Derived>
class TriangularBase;
template <typename MatrixType, unsigned int Mode>
class TriangularView;
template <typename MatrixType, unsigned int Mode>
class SelfAdjointView;
template <typename Derived>
class RealView;
template <typename MatrixType>
class SparseView;
template <typename ExpressionType>
class WithFormat;
template <typename MatrixType>
struct CommaInitializer;
template <typename Derived>
class ReturnByValue;
template <typename ExpressionType>
class ArrayWrapper;
template <typename ExpressionType>
class MatrixWrapper;
template <typename Derived>
class SolverBase;
template <typename XprType>
class InnerIterator;

namespace internal {
template <typename XprType>
class generic_randaccess_stl_iterator;
template <typename XprType>
class pointer_based_stl_iterator;
template <typename XprType, DirectionType Direction>
class subvector_stl_iterator;
template <typename XprType, DirectionType Direction>
class subvector_stl_reverse_iterator;
}  // end namespace internal

namespace internal {
template <typename Scalar_, int Rows = Dynamic, int Cols = Dynamic, int Supers = Dynamic, int Subs = Dynamic,
          int Options = 0>
class BandMatrix;
}

namespace internal {
template <typename Lhs, typename Rhs>
struct product_type;
template <typename Derived, typename Func, typename Identity>
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE typename Derived::Scalar redux_with_identity(const DenseBase<Derived>& xpr,
                                                                                   const Func& func,
                                                                                   Identity&& identity);

/** \internal
 * \class product_evaluator
 * Products need their own evaluator with more template arguments allowing for
 * easier partial template specializations.
 */
template <typename T, int ProductTag = internal::product_type<typename T::Lhs, typename T::Rhs>::value,
          typename LhsShape = typename evaluator_traits<typename T::Lhs>::Shape,
          typename RhsShape = typename evaluator_traits<typename T::Rhs>::Shape,
          typename LhsScalar = typename traits<typename T::Lhs>::Scalar,
          typename RhsScalar = typename traits<typename T::Rhs>::Scalar>
struct product_evaluator;
}  // namespace internal

namespace internal {

// Provides scalar/packet-wise product and product with accumulation
// with optional conjugation of the arguments.
template <typename LhsScalar, typename RhsScalar, bool ConjLhs = false, bool ConjRhs = false>
struct conj_helper;

template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_sum_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_difference_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_conj_product_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar, int NaNPropagation = PropagateFast>
struct scalar_min_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar, int NaNPropagation = PropagateFast>
struct scalar_max_op;
template <typename Scalar>
struct scalar_opposite_op;
template <typename Scalar>
struct scalar_conjugate_op;
template <typename Scalar>
struct scalar_real_op;
template <typename Scalar>
struct scalar_imag_op;
template <typename Scalar>
struct scalar_abs_op;
template <typename Scalar>
struct scalar_abs2_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_absolute_difference_op;
template <typename Scalar>
struct scalar_sqrt_op;
template <typename Scalar>
struct scalar_cbrt_op;
template <typename Scalar>
struct scalar_rsqrt_op;
template <typename Scalar>
struct scalar_exp_op;
template <typename Scalar>
struct scalar_log_op;
template <typename Scalar>
struct scalar_cos_op;
template <typename Scalar>
struct scalar_sin_op;
template <typename Scalar>
struct scalar_acos_op;
template <typename Scalar>
struct scalar_asin_op;
template <typename Scalar>
struct scalar_tan_op;
template <typename Scalar>
struct scalar_atan_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_atan2_op;
template <typename Scalar>
struct scalar_inverse_op;
template <typename Scalar>
struct scalar_square_op;
template <typename Scalar>
struct scalar_cube_op;
template <typename Scalar, typename NewType>
struct scalar_cast_op;
template <typename Scalar>
struct scalar_random_op;
template <typename Scalar>
struct scalar_constant_op;
template <typename Scalar>
struct scalar_identity_op;
template <typename Scalar>
struct scalar_sign_op;
template <typename Scalar, typename ScalarExponent>
struct scalar_pow_op;
template <typename Scalar, typename ScalarExponent, bool BaseIsInteger, bool ExponentIsInteger, bool BaseIsComplex,
          bool ExponentIsComplex>
struct scalar_unary_pow_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_hypot_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_product_op;
template <typename LhsScalar, typename RhsScalar = LhsScalar>
struct scalar_quotient_op;
// logical and bitwise operations
template <typename Scalar>
struct scalar_boolean_and_op;
template <typename Scalar>
struct scalar_boolean_or_op;
template <typename Scalar>
struct scalar_boolean_xor_op;
template <typename Scalar>
struct scalar_boolean_not_op;
template <typename Scalar>
struct scalar_bitwise_and_op;
template <typename Scalar>
struct scalar_bitwise_or_op;
template <typename Scalar>
struct scalar_bitwise_xor_op;
template <typename Scalar>
struct scalar_bitwise_not_op;

// SpecialFunctions module
template <typename Scalar>
struct scalar_lgamma_op;
template <typename Scalar>
struct scalar_digamma_op;
template <typename Scalar>
struct scalar_erf_op;
template <typename Scalar>
struct scalar_erfc_op;
template <typename Scalar>
struct scalar_ndtri_op;
template <typename Scalar>
struct scalar_igamma_op;
template <typename Scalar>
struct scalar_igammac_op;
template <typename Scalar>
struct scalar_zeta_op;
template <typename Scalar>
struct scalar_betainc_op;

// Bessel functions in SpecialFunctions module
template <typename Scalar>
struct scalar_bessel_i0_op;
template <typename Scalar>
struct scalar_bessel_i0e_op;
template <typename Scalar>
struct scalar_bessel_i1_op;
template <typename Scalar>
struct scalar_bessel_i1e_op;
template <typename Scalar>
struct scalar_bessel_j0_op;
template <typename Scalar>
struct scalar_bessel_y0_op;
template <typename Scalar>
struct scalar_bessel_j1_op;
template <typename Scalar>
struct scalar_bessel_y1_op;
template <typename Scalar>
struct scalar_bessel_k0_op;
template <typename Scalar>
struct scalar_bessel_k0e_op;
template <typename Scalar>
struct scalar_bessel_k1_op;
template <typename Scalar>
struct scalar_bessel_k1e_op;

}  // end namespace internal

struct IOFormat;

// Array module
template <typename Scalar_, int Rows_, int Cols_,
          int Options_ = AutoAlign | ((Rows_ == 1 && Cols_ != 1)   ? Eigen::RowMajor
                                      : (Cols_ == 1 && Rows_ != 1) ? Eigen::ColMajor
                                                                   : EIGEN_DEFAULT_MATRIX_STORAGE_ORDER_OPTION),
          int MaxRows_ = Rows_, int MaxCols_ = Cols_>
class Array;
template <typename MatrixType, typename BinaryOp, int Direction>
class PartialReduxExpr;
template <typename ExpressionType, int Direction>
class VectorwiseOp;
template <typename MatrixType, int RowFactor, int ColFactor>
class Replicate;
template <int Direction, typename LhsType, typename RhsType>
class Concat;
template <typename MatrixType, int Direction = BothDirections>
class Reverse;

/* EIGEN_HAS_LAPACK_INT: whether the lapack_int type from the LAPACKE headers is available. Most LAPACKE headers
 * #define lapack_int (so defined(lapack_int) detects it), but some vendors instead expose lapack_int as a typedef
 * and #define LAPACK_INT to advertise it. A user whose header does neither can predefine EIGEN_HAS_LAPACK_INT to
 * 0 or 1 by hand.
 */
#ifndef EIGEN_HAS_LAPACK_INT
#if defined(lapack_int) || defined(LAPACK_INT)
#define EIGEN_HAS_LAPACK_INT 1
#else
#define EIGEN_HAS_LAPACK_INT 0
#endif
#endif

#if defined(EIGEN_USE_LAPACKE) && EIGEN_HAS_LAPACK_INT
// Lapacke interface requires StorageIndex to be lapack_int
using DefaultPermutationIndex = lapack_int;
#else
using DefaultPermutationIndex = int;
#endif

// Plain static_assert (not EIGEN_STATIC_ASSERT): like the MKL_INT guard it must not be suppressible.
#if defined(EIGEN_USE_LAPACKE) && defined(EIGEN_USE_BLAS) && EIGEN_HAS_LAPACK_INT
static_assert(sizeof(lapack_int) == sizeof(BlasIndex),
              "LAPACKE integer width (lapack_int) does not match the BLAS integer width (Eigen::BlasIndex). Build "
              "both backends against the same integer interface: pair EIGEN_64BIT_BLAS with an ILP64 LAPACKE "
              "(lapack_int = 64-bit), or use the 32-bit interface for both.");
#endif

template <typename MatrixType, typename PermutationIndex = DefaultPermutationIndex>
class FullPivLU;
template <typename MatrixType, typename PermutationIndex = DefaultPermutationIndex>
class PartialPivLU;
template <typename MatrixType>
class HouseholderQR;
template <typename MatrixType, typename PermutationIndex = DefaultPermutationIndex>
class ColPivHouseholderQR;
template <typename MatrixType, typename PermutationIndex = DefaultPermutationIndex>
class FullPivHouseholderQR;
template <typename MatrixType, typename PermutationIndex = DefaultPermutationIndex>
class RandColPivHouseholderQR;
template <typename MatrixType, typename PermutationIndex = DefaultPermutationIndex>
class CompleteOrthogonalDecomposition;
template <typename MatrixType, typename PermutationIndex = DefaultPermutationIndex>
class RandCompleteOrthogonalDecomposition;
namespace internal {
template <typename MatrixType, typename PermutationIndex, template <typename, typename> class RankRevealingQR>
class CompleteOrthogonalDecompositionImpl;
}
template <typename MatrixType>
class SVDBase;
template <typename MatrixType, int Options = 0>
class JacobiSVD;
template <typename MatrixType, int Options = 0>
class BDCSVD;
template <typename MatrixType, int UpLo = Lower>
class LLT;
template <typename MatrixType, int UpLo = Lower>
class LDLT;
template <typename MatrixType, int UpLo = Lower>
class BunchKaufman;
template <typename VectorsType, typename CoeffsType, int Side = OnTheLeft>
class HouseholderSequence;
template <typename Scalar>
class JacobiRotation;

// Geometry module:
namespace internal {
template <typename Derived, typename OtherDerived, int Size = MatrixBase<Derived>::SizeAtCompileTime>
struct cross_impl;
}
template <typename Derived, int Dim_>
class RotationBase;
template <typename Derived>
class QuaternionBase;
template <typename Scalar>
class Rotation2D;
template <typename Scalar>
class AngleAxis;
template <typename Scalar, int Dim>
class Translation;
template <typename Scalar, int Dim>
class AlignedBox;
template <typename Scalar, int Options = AutoAlign>
class Quaternion;
template <typename Scalar, int Dim, int Mode, int Options_ = AutoAlign>
class Transform;
template <typename Scalar_, int AmbientDim_, int Options = AutoAlign>
class ParametrizedLine;
template <typename Scalar_, int AmbientDim_, int Options = AutoAlign>
class Hyperplane;
template <typename Scalar>
class UniformScaling;
template <typename MatrixType, int Direction>
class Homogeneous;

// Sparse module:
template <typename Derived>
class SparseMatrixBase;

// MatrixFunctions module
template <typename Derived>
struct MatrixExponentialReturnValue;
template <typename Derived>
class MatrixFunctionReturnValue;
template <typename Derived>
class MatrixSquareRootReturnValue;
template <typename Derived>
class MatrixLogarithmReturnValue;
template <typename Derived>
class MatrixPowerReturnValue;
template <typename Derived>
class MatrixComplexPowerReturnValue;

namespace internal {
template <typename Scalar>
struct stem_function {
  using ComplexScalar = internal::make_complex_t<Scalar>;
  using type = ComplexScalar(ComplexScalar, int);
};
}  // namespace internal

template <typename XprType, typename Device>
struct DeviceWrapper;

namespace internal {
template <typename Xpr>
struct eigen_fill_helper;
template <typename Xpr, bool use_fill = eigen_fill_helper<Xpr>::value>
struct eigen_fill_impl;
template <typename Xpr>
struct eigen_memset_helper;
template <typename Xpr, bool use_memset = eigen_memset_helper<Xpr>::value>
struct eigen_zero_impl;

template <typename Packet>
struct has_packet_segment : std::false_type {};

template <typename T>
struct complex_array_access;
}  // namespace internal

}  // end namespace Eigen

#endif  // EIGEN_FORWARDDECLARATIONS_H