common.h

Go to the documentation of this file.

#ifndef SimTK_SimTKCOMMON_COMMON_H_
#define SimTK_SimTKCOMMON_COMMON_H_

/* -------------------------------------------------------------------------- *
 *                       Simbody(tm): SimTKcommon                             *
 * -------------------------------------------------------------------------- *
 * This is part of the SimTK biosimulation toolkit originating from           *
 * Simbios, the NIH National Center for Physics-Based Simulation of           *
 * Biological Structures at Stanford, funded under the NIH Roadmap for        *
 * Medical Research, grant U54 GM072970. See https://simtk.org/home/simbody.  *
 *                                                                            *
 * Portions copyright (c) 2005-12 Stanford University and the Authors.        *
 * Authors: Michael Sherman                                                   *
 * Contributors:                                                              *
 *                                                                            *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may    *
 * not use this file except in compliance with the License. You may obtain a  *
 * copy of the License at http://www.apache.org/licenses/LICENSE-2.0.         *
 *                                                                            *
 * Unless required by applicable law or agreed to in writing, software        *
 * distributed under the License is distributed on an "AS IS" BASIS,          *
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   *
 * See the License for the specific language governing permissions and        *
 * limitations under the License.                                             *
 * -------------------------------------------------------------------------- */

// Provide doxygen documentation for the SimTK namespace.

// Define shared doxygen "modules" and sub-modules here. We'll put things 
// in them at various places when appropriate.

/*****************************/
/* ANSI-C COMPATIBLE SECTION */
/*****************************/

/* Set up a few compile-time options that affect all SimTK Core headers. */

#ifndef SimTK_DEFAULT_PRECISION
#   define SimTK_DEFAULT_PRECISION 2
#endif

#if   (SimTK_DEFAULT_PRECISION == 1)

    typedef float SimTK_Real;
#elif (SimTK_DEFAULT_PRECISION == 2)

    typedef double SimTK_Real;
#elif (SimTK_DEFAULT_PRECISION == 4)

    typedef long double SimTK_Real;
#else
    #error ILLEGAL VALUE FOR DEFAULT PRECISION
#endif

#ifndef NDEBUG
    #if defined(__cplusplus)
        #include <cstdio>
        #define SimTK_DEBUG(s) std::printf("DBG: " s)
        #define SimTK_DEBUG1(s,a1) std::printf("DBG: " s,a1)    
        #define SimTK_DEBUG2(s,a1,a2) std::printf("DBG: " s,a1,a2)  
        #define SimTK_DEBUG3(s,a1,a2,a3) std::printf("DBG: " s,a1,a2,a3)    
        #define SimTK_DEBUG4(s,a1,a2,a3,a4) std::printf("DBG: " s,a1,a2,a3,a4)
    #else
        #include <stdio.h>
        #define SimTK_DEBUG(s) printf("DBG: " s)
        #define SimTK_DEBUG1(s,a1) printf("DBG: " s,a1) 
        #define SimTK_DEBUG2(s,a1,a2) printf("DBG: " s,a1,a2)   
        #define SimTK_DEBUG3(s,a1,a2,a3) printf("DBG: " s,a1,a2,a3) 
        #define SimTK_DEBUG4(s,a1,a2,a3,a4) printf("DBG: " s,a1,a2,a3,a4)
    #endif
#else
    #define SimTK_DEBUG(s)
    #define SimTK_DEBUG1(s,a1)
    #define SimTK_DEBUG2(s,a1,a2)
    #define SimTK_DEBUG3(s,a1,a2,a3)    
    #define SimTK_DEBUG4(s,a1,a2,a3,a4)
#endif

/*
 * Shared libraries are messy in Visual Studio. We have to distinguish three
 * cases:
 *   (1) this header is being used to build the SimTKcommon shared library (dllexport)
 *   (2) this header is being used by a *client* of the SimTKcommon shared
 *       library (dllimport)
 *   (3) we are building the SimTKcommon static library, or the client is
 *       being compiled with the expectation of linking with the
 *       SimTKcommon static library (nothing special needed)
 * In the CMake script for building this library, we define one of the symbols
 *     SimTK_SimTKCOMMON_BUILDING_{SHARED|STATIC}_LIBRARY
 * Client code normally has no special symbol defined, in which case we'll
 * assume it wants to use the shared library. However, if the client defines
 * the symbol SimTK_USE_STATIC_LIBRARIES we'll suppress the dllimport so
 * that the client code can be linked with static libraries. Note that
 * the client symbol is not library dependent, while the library symbols
 * affect only the SimTKcommon library, meaning that other libraries can
 * be clients of this one. However, we are assuming all-static or all-shared.
 */

#ifdef _WIN32
    #ifdef _MSC_VER
    #pragma warning(disable:4231) /*need to use 'extern' template explicit instantiation*/
    #pragma warning(disable:4251) /*no DLL interface for type of member of exported class*/
    #pragma warning(disable:4275) /*no DLL interface for base class of exported class*/
    #pragma warning(disable:4345) /*warning about PODs being default-initialized*/
    #endif
    #if defined(SimTK_SimTKCOMMON_BUILDING_SHARED_LIBRARY)
        #define SimTK_SimTKCOMMON_EXPORT __declspec(dllexport)
        /* Keep MS VC++ quiet when it tries to instantiate incomplete template classes in a DLL. */
        #ifdef _MSC_VER
        #pragma warning(disable:4661)
        #endif
    #elif defined(SimTK_SimTKCOMMON_BUILDING_STATIC_LIBRARY) || defined(SimTK_USE_STATIC_LIBRARIES)
        #define SimTK_SimTKCOMMON_EXPORT
    #else
        #define SimTK_SimTKCOMMON_EXPORT __declspec(dllimport) /*i.e., a client of a shared library*/
    #endif
    /* VC++ tries to be secure by leaving bounds checking on for STL containers
     * even in Release mode. This macro exists to disable that feature and can
     * result in a considerable speedup.
     * CAUTION: every linked-together compilation unit must have this set the same
     * way. Everyone who properly includes this file first is fine; but as of this
     * writing Simmath's IpOpt doesn't do so.
     * NOTE: Microsoft corrected this problem with VC10 -- the feature is 
     * disabled by default in that compiler and later.
     */
    /* (sherm 081204 disabling for now: doesn't work on VC++ 8 and is 
     * tricky on VC++ 9 because all libraries, including 3rd party, must
     * be built the same way). Better to use the SimTK::Array_<T> class in
     * place of the std::vector<T> class to get better performance.
     #ifdef NDEBUG
        #undef _SECURE_SCL
        #define _SECURE_SCL 0
     #endif
     */
#else
    #define SimTK_SimTKCOMMON_EXPORT // Linux, Mac
#endif

/* Every SimTK Core library must provide these two routines, with the library
 * name appearing after the "version_" and "about_".
 */
#if defined(__cplusplus)
extern "C" {
#endif

    SimTK_SimTKCOMMON_EXPORT void SimTK_version_SimTKcommon(int* major, int* minor, int* build);
    SimTK_SimTKCOMMON_EXPORT void SimTK_about_SimTKcommon(const char* key, int maxlen, char* value);
#if defined(__cplusplus)
}
#endif

/************************************/
/* END OF ANSI-C COMPATIBLE SECTION */
/************************************/

#if defined(__cplusplus)

#include <cstddef>
#include <cassert>
#include <cmath>
#include <cfloat>
#include <complex>
#include <limits>
#include <typeinfo>

/* Transition macros for C++11 support. VC10 and VC11 have partial support for
C++11, early VC's do not. Currently we're assuming no support from gcc. */
#ifndef SWIG
    #if _MSC_VER>=1700 /* VC11 or higher */
        #define OVERRIDE_11  override
        #define FINAL_11     final
    #elif _MSC_VER==1600 /* VC10 */
        #define OVERRIDE_11  override
        #define FINAL_11     sealed
    #else /* gcc or earlier VC */
        #define OVERRIDE_11
        #define FINAL_11
    #endif
#else /* Swigging */
    #define OVERRIDE_11
    #define FINAL_11
#endif


/* Currently (Microsoft VC++ 9) these C99-compatible floating point functions 
are missing. We'll create them here and install them into namespace std.
TODO: This should be removed when these are available. */
#ifdef _MSC_VER
namespace std {
inline bool isfinite(float f) {return _finite(f) != 0;}
inline bool isfinite(double d) {return _finite(d) != 0;}
inline bool isfinite(long double l) {return _finite(l) != 0;}
inline bool isnan(float f) {return _isnan(f) != 0;}
inline bool isnan(double d) {return _isnan(d) != 0;}
inline bool isnan(long double l) {return _isnan(l) != 0;}
inline bool isinf(float f) {return std::abs(f)==std::numeric_limits<float>::infinity();}
inline bool isinf(double d) {return std::abs(d)==std::numeric_limits<double>::infinity();}
inline bool isinf(long double l) {return std::abs(l)==std::numeric_limits<double>::infinity();}
inline bool signbit(float f) {return (*reinterpret_cast<unsigned*>(&f) & 0x80000000U) != 0;}
inline bool signbit(double d) {return (*reinterpret_cast<unsigned long long*>(&d)
                               & 0x8000000000000000ULL) != 0;}
inline bool signbit(long double l) {return (*reinterpret_cast<unsigned long long*>(&l)
                                    & 0x8000000000000000ULL) != 0;}
}
#endif


namespace SimTK {


// This utility answers the question "if I put this integral value in an int and then
// get it back, will its value be the same?".
inline bool canStoreInInt(bool)            {return true;}
inline bool canStoreInInt(char)            {return true;}
inline bool canStoreInInt(unsigned char)   {return true;}
inline bool canStoreInInt(signed char)     {return true;}
inline bool canStoreInInt(short)           {return true;}
inline bool canStoreInInt(unsigned short)  {return true;}
inline bool canStoreInInt(int)             {return true;}
inline bool canStoreInInt(unsigned int  u) {return (unsigned int)(int(u)) == u;}
inline bool canStoreInInt(long i)          {return long(int(i)) == i;}
inline bool canStoreInInt(unsigned long u) {return (unsigned long)(int(u)) == u;}
inline bool canStoreInInt(long long i)          {return (long long)(int(i)) == i;}
inline bool canStoreInInt(unsigned long long u) {return (unsigned long long)(int(u)) == u;}

// This utility answers the question "is this integral value a nonnegative number
// that can be stored in an int?".
inline bool canStoreInNonnegativeInt(bool)             {return true;}
inline bool canStoreInNonnegativeInt(char c)           {return c >= 0;}
inline bool canStoreInNonnegativeInt(unsigned char)    {return true;}
inline bool canStoreInNonnegativeInt(signed char c)    {return c >= 0;}
inline bool canStoreInNonnegativeInt(short s)          {return s >= 0;}
inline bool canStoreInNonnegativeInt(unsigned short)   {return true;}
inline bool canStoreInNonnegativeInt(int  i)           {return i >= 0;}
inline bool canStoreInNonnegativeInt(long l)           {return canStoreInInt(l) && l >= 0;}
inline bool canStoreInNonnegativeInt(long long l)      {return canStoreInInt(l) && l >= 0;}
inline bool canStoreInNonnegativeInt(unsigned int  u)  {return canStoreInInt(u);}
inline bool canStoreInNonnegativeInt(unsigned long u)  {return canStoreInInt(u);}
inline bool canStoreInNonnegativeInt(unsigned long long u) {return canStoreInInt(u);}

// This utility answers the question of whether an integer is suitable as a size
// limited by the given maximum size. Signed types must be checked for being
// nonegative; doing that with unsigned types leads to compiler warnings.

// char can be signed or unsigned depending on the compiler; assume signed.
inline bool isSizeInRange(char           sz, char           mx){return 0<=sz&&sz<=mx;}
inline bool isSizeInRange(signed char    sz, signed char    mx){return 0<=sz&&sz<=mx;}
inline bool isSizeInRange(short          sz, short          mx){return 0<=sz&&sz<=mx;}
inline bool isSizeInRange(int            sz, int            mx){return 0<=sz&&sz<=mx;}
inline bool isSizeInRange(long           sz, long           mx){return 0<=sz&&sz<=mx;}
inline bool isSizeInRange(long long      sz, long long      mx){return 0<=sz&&sz<=mx;}
inline bool isSizeInRange(unsigned char  sz, unsigned char  mx){return sz<=mx;}
inline bool isSizeInRange(unsigned short sz, unsigned short mx){return sz<=mx;}
inline bool isSizeInRange(unsigned int   sz, unsigned int   mx){return sz<=mx;}
inline bool isSizeInRange(unsigned long  sz, unsigned long  mx){return sz<=mx;}
inline bool isSizeInRange(unsigned long long sz, unsigned long long mx){return sz<=mx;}

// This utility answers the question of whether an integer is suitable as an index
// for an array limited by the given maximum size. Signed types must be checked for being
// nonegative; doing that with unsigned types leads to compiler warnings. This is just
// like the "size in range" check above except the maximum value allowed for an index
// is one less that the size.

// char can be signed or unsigned depending on the compiler; assume signed.
inline bool isIndexInRange(char           ix, char           sz){return 0<=ix&&ix<sz;}
inline bool isIndexInRange(signed char    ix, signed char    sz){return 0<=ix&&ix<sz;}
inline bool isIndexInRange(short          ix, short          sz){return 0<=ix&&ix<sz;}
inline bool isIndexInRange(int            ix, int            sz){return 0<=ix&&ix<sz;}
inline bool isIndexInRange(long           ix, long           sz){return 0<=ix&&ix<sz;}
inline bool isIndexInRange(long long      ix, long long      sz){return 0<=ix&&ix<sz;}
inline bool isIndexInRange(unsigned char  ix, unsigned char  sz){return ix<sz;}
inline bool isIndexInRange(unsigned short ix, unsigned short sz){return ix<sz;}
inline bool isIndexInRange(unsigned int   ix, unsigned int   sz){return ix<sz;}
inline bool isIndexInRange(unsigned long  ix, unsigned long  sz){return ix<sz;}
inline bool isIndexInRange(unsigned long long ix, unsigned long long sz){return ix<sz;}

// This utility answers the question: is this integral value nonnegative? The answer
// is always true for unsigned types and you'll get a warning from some compilers if
// you check.

inline bool isNonnegative(bool)              {return true;}
// char can be signed or unsigned depending on the compiler; assume signed.
inline bool isNonnegative(char        n)     {return n>=0;}
inline bool isNonnegative(signed char n)     {return n>=0;}
inline bool isNonnegative(short       n)     {return n>=0;}
inline bool isNonnegative(int         n)     {return n>=0;}
inline bool isNonnegative(long        n)     {return n>=0;}
inline bool isNonnegative(long long   n)     {return n>=0;}
inline bool isNonnegative(unsigned char)     {return true;}
inline bool isNonnegative(unsigned short)    {return true;}
inline bool isNonnegative(unsigned int)      {return true;}
inline bool isNonnegative(unsigned long)     {return true;}
inline bool isNonnegative(unsigned long long){return true;}

// A NaN-like value for unique index types created using the macro
// SimTK_DEFINE_UNIQUE_INDEX_TYPE(). A unique, typed constant with
// this numerical value is created for each index type.
static const int InvalidIndex = -1111111111;
}



#define SimTK_DEFINE_UNIQUE_INDEX_TYPE(NAME)                   \
    SimTK_DEFINE_AND_EXPORT_UNIQUE_LOCAL_INDEX_TYPE(,,,NAME)   \
    static const NAME Invalid ## NAME;

#define SimTK_DEFINE_AND_EXPORT_UNIQUE_INDEX_TYPE(EXPORT,NAME)     \
    SimTK_DEFINE_AND_EXPORT_UNIQUE_LOCAL_INDEX_TYPE(EXPORT,,,NAME) \
    static const NAME Invalid ## NAME;

#define SimTK_DEFINE_UNIQUE_LOCAL_INDEX_TYPE(PARENT,NAME) \
    SimTK_DEFINE_AND_EXPORT_UNIQUE_LOCAL_INDEX_TYPE(,PARENT,::,NAME)

#define SimTK_DEFINE_AND_EXPORT_UNIQUE_LOCAL_INDEX_TYPE(EXPORT,PARENT,SEP,NAME)   \
class EXPORT NAME {                         \
    int ix;                                 \
public:                                     \
    NAME() : ix(SimTK::InvalidIndex) { }       \
    explicit NAME(int i) : ix(i)      {assert(i>=0 || i==SimTK::InvalidIndex);} \
    explicit NAME(long l): ix((int)l) {assert(SimTK::canStoreInNonnegativeInt(l));}    \
    explicit NAME(unsigned int  u)  : ix((int)u)  {assert(SimTK::canStoreInInt(u));}   \
    explicit NAME(unsigned long ul) : ix((int)ul) {assert(SimTK::canStoreInInt(ul));}  \
    operator int() const {return ix;}               \
    bool isValid() const {return ix>=0;}            \
    bool isValidExtended() const {return ix>=-1;}   \
    void invalidate(){ix=SimTK::InvalidIndex;}      \
    \
    bool operator==(int  i) const {assert(isValidExtended() && isValidExtended(i)); return ix==i;}    \
    bool operator==(short s) const{assert(isValidExtended() && isValidExtended(s)); return ix==(int)s;}  \
    bool operator==(long l) const {assert(isValidExtended() && isValidExtended(l)); return ix==(int)l;}  \
    bool operator==(unsigned int  u)  const {assert(isValidExtended() && isValid(u)); return ix==(int)u;}   \
    bool operator==(unsigned short us)const {assert(isValidExtended() && isValid(us)); return ix==(int)us;} \
    bool operator==(unsigned long ul) const {assert(isValidExtended() && isValid(ul)); return ix==(int)ul;} \
    bool operator!=(int  i)           const {return !operator==(i);}    \
    bool operator!=(short s)          const {return !operator==(s);}    \
    bool operator!=(long l)           const {return !operator==(l);}    \
    bool operator!=(unsigned int  u)  const {return !operator==(u);}    \
    bool operator!=(unsigned long ul) const {return !operator==(ul);}   \
    \
    bool operator< (int  i) const {assert(isValidExtended() && isValidExtended(i)); return ix<i;}        \
    bool operator< (short s) const{assert(isValidExtended() && isValidExtended(s)); return ix<(int)s;}   \
    bool operator< (long l) const {assert(isValidExtended() && isValidExtended(l)); return ix<(int)l;}   \
    bool operator< (unsigned int  u)  const {assert(isValidExtended() && isValid(u));  return ix<(int)u;}    \
    bool operator< (unsigned short us)const {assert(isValidExtended() && isValid(us)); return ix<(int)us;}   \
    bool operator< (unsigned long ul) const {assert(isValidExtended() && isValid(ul)); return ix<(int)ul;}   \
    bool operator>=(int  i)           const {return !operator<(i);}    \
    bool operator>=(short s)          const {return !operator<(s);}    \
    bool operator>=(long l)           const {return !operator<(l);}    \
    bool operator>=(unsigned int  u)  const {return !operator<(u);}    \
    bool operator>=(unsigned short us)const {return !operator<(us);}   \
    bool operator>=(unsigned long ul) const {return !operator<(ul);}   \
    \
    bool operator> (int  i) const {assert(isValidExtended() && isValidExtended(i)); return ix>i;}        \
    bool operator> (short s) const{assert(isValidExtended() && isValidExtended(s)); return ix>(int)s;}   \
    bool operator> (long l) const {assert(isValidExtended() && isValidExtended(l)); return ix>(int)l;}   \
    bool operator> (unsigned int  u)  const {assert(isValidExtended() && isValid(u));  return ix>(int)u;}    \
    bool operator> (unsigned short us)const {assert(isValidExtended() && isValid(us)); return ix>(int)us;}   \
    bool operator> (unsigned long ul) const {assert(isValidExtended() && isValid(ul)); return ix>(int)ul;}   \
    bool operator<=(int  i)           const {return !operator>(i);}    \
    bool operator<=(short s)          const {return !operator>(s);}    \
    bool operator<=(long l)           const {return !operator>(l);}    \
    bool operator<=(unsigned int  u)  const {return !operator>(u);}    \
    bool operator<=(unsigned short us)const {return !operator>(us);}   \
    bool operator<=(unsigned long ul) const {return !operator>(ul);}   \
    \
    const NAME& operator++() {assert(isValid()); ++ix; return *this;}       /*prefix */   \
    NAME operator++(int)     {assert(isValid()); ++ix; return NAME(ix-1);}  /*postfix*/   \
    const NAME& operator--() {assert(isValid()); --ix; return *this;}       /*prefix */   \
    NAME operator--(int)     {assert(isValid()); --ix; return NAME(ix+1);}  /*postfix*/   \
    NAME next() const {assert(isValid()); return NAME(ix+1);}                             \
    NAME prev() const {assert(isValid()); return NAME(ix-1);} /*might return -1*/         \
    \
    NAME& operator+=(int i)  {assert(isValid() && isValidExtended(ix+i)); ix+=i; return *this;}     \
    NAME& operator-=(int i)  {assert(isValid() && isValidExtended(ix-i)); ix-=i; return *this;}     \
    NAME& operator+=(short s){assert(isValid() && SimTK::canStoreInInt(s) && isValidExtended(ix+(int)s)); ix+=(int)s; return *this;}     \
    NAME& operator-=(short s){assert(isValid() && SimTK::canStoreInInt(s) && isValidExtended(ix-(int)s)); ix-=(int)s; return *this;}     \
    NAME& operator+=(long l) {assert(isValid() && SimTK::canStoreInInt(l) && isValidExtended(ix+(int)l)); ix+=(int)l; return *this;}     \
    NAME& operator-=(long l) {assert(isValid() && SimTK::canStoreInInt(l) && isValidExtended(ix-(int)l)); ix-=(int)l; return *this;}     \
    NAME& operator+=(unsigned int  u)  {assert(isValid()&& SimTK::canStoreInInt(u)  && isValid(ix+(int)u));  ix+=(int)u;  return *this;}  \
    NAME& operator-=(unsigned int  u)  {assert(isValid()&& SimTK::canStoreInInt(u)  && isValidExtended(ix-(int)u));  ix-=(int)u;  return *this;}  \
    NAME& operator+=(unsigned short us){assert(isValid()&& SimTK::canStoreInInt(us) && isValid(ix+(int)us)); ix+=(int)us; return *this;}  \
    NAME& operator-=(unsigned short us){assert(isValid()&& SimTK::canStoreInInt(us) && isValidExtended(ix-(int)us)); ix-=(int)us; return *this;}  \
    NAME& operator+=(unsigned long ul) {assert(isValid()&& SimTK::canStoreInInt(ul) && isValid(ix+(int)ul)); ix+=(int)ul; return *this;}  \
    NAME& operator-=(unsigned long ul) {assert(isValid()&& SimTK::canStoreInInt(ul) && isValidExtended(ix-(int)ul)); ix-=(int)ul; return *this;}  \
    \
    static const NAME& Invalid() {static const NAME invalid; return invalid;}       \
    static bool isValid(int  i) {return i>=0;}                                      \
    static bool isValid(short s){return s>=0;}                                      \
    static bool isValid(long l) {return SimTK::canStoreInNonnegativeInt(l);}        \
    static bool isValid(unsigned int  u)  {return SimTK::canStoreInInt(u);}         \
    static bool isValid(unsigned short)   {return true;}                            \
    static bool isValid(unsigned long ul) {return SimTK::canStoreInInt(ul);}        \
    static bool isValidExtended(int  i) {return i>=-1;}                             \
    static bool isValidExtended(short s){return s>=-1;}                             \
    static bool isValidExtended(long l) {return SimTK::canStoreInInt(l) && l>=-1;}  \
    /* IndexTraits for use in Array_<T,X> with this as X; same as int */            \
    typedef int size_type;                                                  \
    typedef int difference_type;                                            \
    static size_type max_size() {return std::numeric_limits<int>::max();}   \
};

#ifndef NDEBUG
    #define SimTK_DYNAMIC_CAST_DEBUG dynamic_cast   // safe but slow
#else
    #define SimTK_DYNAMIC_CAST_DEBUG static_cast    // unsafe but fast
#endif

#define SimTK_DOWNCAST(Derived,Parent)                          \
    static bool isA(const Parent& p)                            \
        { return dynamic_cast<const Derived*>(&p) != 0; }       \
    static const Derived& downcast(const Parent& p)             \
        { return SimTK_DYNAMIC_CAST_DEBUG<const Derived&>(p); } \
    static Derived& updDowncast(Parent& p)                      \
        { return SimTK_DYNAMIC_CAST_DEBUG<Derived&>(p); }       \
    static Derived& downcast(Parent& p)                         \
        { return SimTK_DYNAMIC_CAST_DEBUG<Derived&>(p); }

#define SimTK_DOWNCAST2(Derived,Helper,Parent)                          \
    static bool isA(const Parent& p)                                    \
        { return Helper::isA(p); }                                      \
    static const Derived& downcast(const Parent& p)                     \
        { return static_cast<const Derived&>(Helper::downcast(p)); }    \
    static Derived& updDowncast(Parent& p)                              \
        { return static_cast<Derived&>(Helper::downcast(p)); }          \
    static Derived& downcast(Parent& p)                                 \
        { return static_cast<Derived&>(Helper::downcast(p)); }


#define SimTK_PIMPL_DOWNCAST(Derived, Parent)           \
    static bool           isInstanceOf(const Parent&);  \
    static const Derived& downcast(const Parent&);      \
    static Derived&       updDowncast(Parent&)

namespace SimTK {

namespace Exception { }

typedef SimTK_Real              Real;
typedef std::complex<Real>      Complex;
typedef std::complex<float>     fComplex;
typedef std::complex<float>     dComplex;


// Forward declaration giving template defaults must come before any
// other declarations.
template <int M, class E=Real, int STRIDE=1>              class Vec;
template <int N, class E=Real, int STRIDE=1>              class Row; 
template <int M, int N, class E=Real, int CS=M, int RS=1> class Mat; // col & row spacing
template <int M, class E=Real, int RS=1>                  class SymMat;


struct Segment {
    Segment() : length(0), offset(0) { }
    explicit Segment(int l, int ofs=0) : length(l), offset(ofs) { 
        assert(l>=0 && ofs>=0);
    }
    // default copy, assignment, destructor
    int length;
    int offset;
};  


struct DontCopy {};
struct TrustMe {};

struct FalseType {};
struct TrueType {};

template <class L, class R> struct AndOpType {};
template<> struct AndOpType<FalseType,FalseType> {typedef FalseType Result;};
template<> struct AndOpType<FalseType,TrueType>  {typedef FalseType Result;};
template<> struct AndOpType<TrueType, FalseType> {typedef FalseType Result;};
template<> struct AndOpType<TrueType, TrueType>  {typedef TrueType  Result;};

template <class L, class R> struct OrOpType {};
template<> struct OrOpType<FalseType,FalseType> {typedef FalseType Result;};
template<> struct OrOpType<FalseType,TrueType>  {typedef TrueType  Result;};
template<> struct OrOpType<TrueType, FalseType> {typedef TrueType  Result;};
template<> struct OrOpType<TrueType, TrueType>  {typedef TrueType  Result;};

template <class L, class R> struct XorOpType {};
template<> struct XorOpType<FalseType,FalseType> {typedef FalseType Result;};
template<> struct XorOpType<FalseType,TrueType>  {typedef TrueType  Result;};
template<> struct XorOpType<TrueType, FalseType> {typedef TrueType  Result;};
template<> struct XorOpType<TrueType, TrueType>  {typedef FalseType Result;};

template <class T> struct IsIntegralType {
    typedef FalseType Result;
    static const bool result = false;
};
#define SimTK_SPECIALIZE_INTEGRAL_TYPE(T)       \
    template<> struct IsIntegralType<T>         \
    {typedef TrueType Result; static const bool result = true;}

SimTK_SPECIALIZE_INTEGRAL_TYPE(bool); 
SimTK_SPECIALIZE_INTEGRAL_TYPE(char);
// This causes problems when used with Qt which for some crazy
// reason likes to make its own wchar_t rather than using the built in.
// SimTK_SPECIALIZE_INTEGRAL_TYPE(wchar_t);
SimTK_SPECIALIZE_INTEGRAL_TYPE(signed char);
SimTK_SPECIALIZE_INTEGRAL_TYPE(unsigned char);
SimTK_SPECIALIZE_INTEGRAL_TYPE(short);
SimTK_SPECIALIZE_INTEGRAL_TYPE(unsigned short);
SimTK_SPECIALIZE_INTEGRAL_TYPE(int);
SimTK_SPECIALIZE_INTEGRAL_TYPE(unsigned int); // a.k.a. "unsigned"
SimTK_SPECIALIZE_INTEGRAL_TYPE(long);
SimTK_SPECIALIZE_INTEGRAL_TYPE(unsigned long);
SimTK_SPECIALIZE_INTEGRAL_TYPE(long long);
SimTK_SPECIALIZE_INTEGRAL_TYPE(unsigned long long);

template <class T> struct IsFloatingType {
    typedef FalseType Result;
    static const bool result = false;
};
#define SimTK_SPECIALIZE_FLOATING_TYPE(T)       \
    template<> struct IsFloatingType<T>         \
    {typedef TrueType Result; static const bool result = true;}

SimTK_SPECIALIZE_FLOATING_TYPE(float); 
SimTK_SPECIALIZE_FLOATING_TYPE(double); 
SimTK_SPECIALIZE_FLOATING_TYPE(long double); 

template <class T> struct IsVoidType {
    typedef FalseType Result;
    static const bool result = false;
};
template<> struct IsVoidType<void> 
{typedef TrueType Result; static const bool result = true;};

template <class T> struct IsArithmeticType {
    typedef OrOpType<typename IsIntegralType<T>::Result,
                     typename IsFloatingType<T>::Result>    Result;
    static const bool result = IsIntegralType<T>::result 
                            || IsFloatingType<T>::result;
};

// This struct's sole use is to allow us to define the typedef 
// Is64BitPlatformType as equivalent to either TrueType or FalseType.
template <bool is64Bit> struct Is64BitHelper {};
template<> struct Is64BitHelper<true>  
{typedef TrueType  Result; static const bool result = true;};
template<> struct Is64BitHelper<false> 
{typedef FalseType Result; static const bool result = false;};

static const bool Is64BitPlatform = sizeof(size_t) > sizeof(int);
typedef Is64BitHelper<Is64BitPlatform>::Result Is64BitPlatformType;


template <class T> struct NiceTypeName {
    static const char* name() {return typeid(T).name();}
};

#define SimTK_NICETYPENAME_LITERAL(T)           \
template <> struct NiceTypeName< T > {          \
    static const char* name() { return #T; }    \
};

// Some types for which we'd like to see nice type names.
SimTK_NICETYPENAME_LITERAL(bool);            
SimTK_NICETYPENAME_LITERAL(char); 
// This causes problems when used with Qt which for some crazy
// reason likes to make its own wchar_t rather than using the built in.
// SimTK_NICETYPENAME_LITERAL(wchar_t);            
SimTK_NICETYPENAME_LITERAL(signed char); 
SimTK_NICETYPENAME_LITERAL(unsigned char);
SimTK_NICETYPENAME_LITERAL(short);           
SimTK_NICETYPENAME_LITERAL(unsigned short);  
SimTK_NICETYPENAME_LITERAL(int); 
SimTK_NICETYPENAME_LITERAL(unsigned); // preferred to "unsigned int"
SimTK_NICETYPENAME_LITERAL(long);            
SimTK_NICETYPENAME_LITERAL(unsigned long);   
SimTK_NICETYPENAME_LITERAL(long long);
SimTK_NICETYPENAME_LITERAL(unsigned long long);
SimTK_NICETYPENAME_LITERAL(float);           
SimTK_NICETYPENAME_LITERAL(double); 
SimTK_NICETYPENAME_LITERAL(long double);
SimTK_NICETYPENAME_LITERAL(std::string);
SimTK_NICETYPENAME_LITERAL(std::complex<float>);
SimTK_NICETYPENAME_LITERAL(std::complex<double>); 
SimTK_NICETYPENAME_LITERAL(std::complex<long double>); 
SimTK_NICETYPENAME_LITERAL(SimTK::FalseType);
SimTK_NICETYPENAME_LITERAL(SimTK::TrueType); 

} // namespace SimTK

#endif /* C++ stuff */

#endif /* SimTK_SimTKCOMMON_COMMON_H_ */