You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and dots ('.'), can be up to 35 characters long. Letters must be lowercase.
509 lines
14 KiB
509 lines
14 KiB
#ifndef _DATE_TIME_INT_ADAPTER_HPP__ |
|
#define _DATE_TIME_INT_ADAPTER_HPP__ |
|
|
|
/* Copyright (c) 2002,2003 CrystalClear Software, Inc. |
|
* Use, modification and distribution is subject to the |
|
* Boost Software License, Version 1.0. (See accompanying |
|
* file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt) |
|
* Author: Jeff Garland, Bart Garst |
|
* $Date: 2008-11-12 14:37:53 -0500 (Wed, 12 Nov 2008) $ |
|
*/ |
|
|
|
|
|
#include "boost/config.hpp" |
|
#include "boost/limits.hpp" //work around compilers without limits |
|
#include "boost/date_time/special_defs.hpp" |
|
#include "boost/date_time/locale_config.hpp" |
|
#ifndef BOOST_DATE_TIME_NO_LOCALE |
|
# include <ostream> |
|
#endif |
|
|
|
namespace boost { |
|
namespace date_time { |
|
|
|
|
|
//! Adapter to create integer types with +-infinity, and not a value |
|
/*! This class is used internally in counted date/time representations. |
|
* It adds the floating point like features of infinities and |
|
* not a number. It also provides mathmatical operations with |
|
* consideration to special values following these rules: |
|
*@code |
|
* +infinity - infinity == Not A Number (NAN) |
|
* infinity * non-zero == infinity |
|
* infinity * zero == NAN |
|
* +infinity * -integer == -infinity |
|
* infinity / infinity == NAN |
|
* infinity * infinity == infinity |
|
*@endcode |
|
*/ |
|
template<typename int_type_> |
|
class int_adapter { |
|
public: |
|
typedef int_type_ int_type; |
|
int_adapter(int_type v) : |
|
value_(v) |
|
{} |
|
static bool has_infinity() |
|
{ |
|
return true; |
|
} |
|
static const int_adapter pos_infinity() |
|
{ |
|
return (::std::numeric_limits<int_type>::max)(); |
|
} |
|
static const int_adapter neg_infinity() |
|
{ |
|
return (::std::numeric_limits<int_type>::min)(); |
|
} |
|
static const int_adapter not_a_number() |
|
{ |
|
return (::std::numeric_limits<int_type>::max)()-1; |
|
} |
|
static int_adapter max BOOST_PREVENT_MACRO_SUBSTITUTION () |
|
{ |
|
return (::std::numeric_limits<int_type>::max)()-2; |
|
} |
|
static int_adapter min BOOST_PREVENT_MACRO_SUBSTITUTION () |
|
{ |
|
return (::std::numeric_limits<int_type>::min)()+1; |
|
} |
|
static int_adapter from_special(special_values sv) |
|
{ |
|
switch (sv) { |
|
case not_a_date_time: return not_a_number(); |
|
case neg_infin: return neg_infinity(); |
|
case pos_infin: return pos_infinity(); |
|
case max_date_time: return (max)(); |
|
case min_date_time: return (min)(); |
|
default: return not_a_number(); |
|
} |
|
} |
|
static bool is_inf(int_type v) |
|
{ |
|
return (v == neg_infinity().as_number() || |
|
v == pos_infinity().as_number()); |
|
} |
|
static bool is_neg_inf(int_type v) |
|
{ |
|
return (v == neg_infinity().as_number()); |
|
} |
|
static bool is_pos_inf(int_type v) |
|
{ |
|
return (v == pos_infinity().as_number()); |
|
} |
|
static bool is_not_a_number(int_type v) |
|
{ |
|
return (v == not_a_number().as_number()); |
|
} |
|
//! Returns either special value type or is_not_special |
|
static special_values to_special(int_type v) |
|
{ |
|
if (is_not_a_number(v)) return not_a_date_time; |
|
if (is_neg_inf(v)) return neg_infin; |
|
if (is_pos_inf(v)) return pos_infin; |
|
return not_special; |
|
} |
|
|
|
//-3 leaves room for representations of infinity and not a date |
|
static int_type maxcount() |
|
{ |
|
return (::std::numeric_limits<int_type>::max)()-3; |
|
} |
|
bool is_infinity() const |
|
{ |
|
return (value_ == neg_infinity().as_number() || |
|
value_ == pos_infinity().as_number()); |
|
} |
|
bool is_pos_infinity()const |
|
{ |
|
return(value_ == pos_infinity().as_number()); |
|
} |
|
bool is_neg_infinity()const |
|
{ |
|
return(value_ == neg_infinity().as_number()); |
|
} |
|
bool is_nan() const |
|
{ |
|
return (value_ == not_a_number().as_number()); |
|
} |
|
bool is_special() const |
|
{ |
|
return(is_infinity() || is_nan()); |
|
} |
|
bool operator==(const int_adapter& rhs) const |
|
{ |
|
return (compare(rhs) == 0); |
|
} |
|
bool operator==(const int& rhs) const |
|
{ |
|
// quiets compiler warnings |
|
bool is_signed = std::numeric_limits<int_type>::is_signed; |
|
if(!is_signed) |
|
{ |
|
if(is_neg_inf(value_) && rhs == 0) |
|
{ |
|
return false; |
|
} |
|
} |
|
return (compare(rhs) == 0); |
|
} |
|
bool operator!=(const int_adapter& rhs) const |
|
{ |
|
return (compare(rhs) != 0); |
|
} |
|
bool operator!=(const int& rhs) const |
|
{ |
|
// quiets compiler warnings |
|
bool is_signed = std::numeric_limits<int_type>::is_signed; |
|
if(!is_signed) |
|
{ |
|
if(is_neg_inf(value_) && rhs == 0) |
|
{ |
|
return true; |
|
} |
|
} |
|
return (compare(rhs) != 0); |
|
} |
|
bool operator<(const int_adapter& rhs) const |
|
{ |
|
return (compare(rhs) == -1); |
|
} |
|
bool operator<(const int& rhs) const |
|
{ |
|
// quiets compiler warnings |
|
bool is_signed = std::numeric_limits<int_type>::is_signed; |
|
if(!is_signed) |
|
{ |
|
if(is_neg_inf(value_) && rhs == 0) |
|
{ |
|
return true; |
|
} |
|
} |
|
return (compare(rhs) == -1); |
|
} |
|
bool operator>(const int_adapter& rhs) const |
|
{ |
|
return (compare(rhs) == 1); |
|
} |
|
int_type as_number() const |
|
{ |
|
return value_; |
|
} |
|
//! Returns either special value type or is_not_special |
|
special_values as_special() const |
|
{ |
|
return int_adapter::to_special(value_); |
|
} |
|
//creates nasty ambiguities |
|
// operator int_type() const |
|
// { |
|
// return value_; |
|
// } |
|
|
|
/*! Operator allows for adding dissimilar int_adapter types. |
|
* The return type will match that of the the calling object's type */ |
|
template<class rhs_type> |
|
inline |
|
int_adapter operator+(const int_adapter<rhs_type>& rhs) const |
|
{ |
|
if(is_special() || rhs.is_special()) |
|
{ |
|
if (is_nan() || rhs.is_nan()) |
|
{ |
|
return int_adapter::not_a_number(); |
|
} |
|
if((is_pos_inf(value_) && rhs.is_neg_inf(rhs.as_number())) || |
|
(is_neg_inf(value_) && rhs.is_pos_inf(rhs.as_number())) ) |
|
{ |
|
return int_adapter::not_a_number(); |
|
} |
|
if (is_infinity()) |
|
{ |
|
return *this; |
|
} |
|
if (rhs.is_pos_inf(rhs.as_number())) |
|
{ |
|
return int_adapter::pos_infinity(); |
|
} |
|
if (rhs.is_neg_inf(rhs.as_number())) |
|
{ |
|
return int_adapter::neg_infinity(); |
|
} |
|
} |
|
return int_adapter<int_type>(value_ + rhs.as_number()); |
|
} |
|
|
|
int_adapter operator+(const int_type rhs) const |
|
{ |
|
if(is_special()) |
|
{ |
|
if (is_nan()) |
|
{ |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
if (is_infinity()) |
|
{ |
|
return *this; |
|
} |
|
} |
|
return int_adapter<int_type>(value_ + rhs); |
|
} |
|
|
|
/*! Operator allows for subtracting dissimilar int_adapter types. |
|
* The return type will match that of the the calling object's type */ |
|
template<class rhs_type> |
|
inline |
|
int_adapter operator-(const int_adapter<rhs_type>& rhs)const |
|
{ |
|
if(is_special() || rhs.is_special()) |
|
{ |
|
if (is_nan() || rhs.is_nan()) |
|
{ |
|
return int_adapter::not_a_number(); |
|
} |
|
if((is_pos_inf(value_) && rhs.is_pos_inf(rhs.as_number())) || |
|
(is_neg_inf(value_) && rhs.is_neg_inf(rhs.as_number())) ) |
|
{ |
|
return int_adapter::not_a_number(); |
|
} |
|
if (is_infinity()) |
|
{ |
|
return *this; |
|
} |
|
if (rhs.is_pos_inf(rhs.as_number())) |
|
{ |
|
return int_adapter::neg_infinity(); |
|
} |
|
if (rhs.is_neg_inf(rhs.as_number())) |
|
{ |
|
return int_adapter::pos_infinity(); |
|
} |
|
} |
|
return int_adapter<int_type>(value_ - rhs.as_number()); |
|
} |
|
int_adapter operator-(const int_type rhs) const |
|
{ |
|
if(is_special()) |
|
{ |
|
if (is_nan()) |
|
{ |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
if (is_infinity()) |
|
{ |
|
return *this; |
|
} |
|
} |
|
return int_adapter<int_type>(value_ - rhs); |
|
} |
|
|
|
// should templatize this to be consistant with op +- |
|
int_adapter operator*(const int_adapter& rhs)const |
|
{ |
|
if(this->is_special() || rhs.is_special()) |
|
{ |
|
return mult_div_specials(rhs); |
|
} |
|
return int_adapter<int_type>(value_ * rhs.value_); |
|
} |
|
/*! Provided for cases when automatic conversion from |
|
* 'int' to 'int_adapter' causes incorrect results. */ |
|
int_adapter operator*(const int rhs) const |
|
{ |
|
if(is_special()) |
|
{ |
|
return mult_div_specials(rhs); |
|
} |
|
return int_adapter<int_type>(value_ * rhs); |
|
} |
|
|
|
// should templatize this to be consistant with op +- |
|
int_adapter operator/(const int_adapter& rhs)const |
|
{ |
|
if(this->is_special() || rhs.is_special()) |
|
{ |
|
if(is_infinity() && rhs.is_infinity()) |
|
{ |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
if(rhs != 0) |
|
{ |
|
return mult_div_specials(rhs); |
|
} |
|
else { // let divide by zero blow itself up |
|
return int_adapter<int_type>(value_ / rhs.value_); |
|
} |
|
} |
|
return int_adapter<int_type>(value_ / rhs.value_); |
|
} |
|
/*! Provided for cases when automatic conversion from |
|
* 'int' to 'int_adapter' causes incorrect results. */ |
|
int_adapter operator/(const int rhs) const |
|
{ |
|
if(is_special() && rhs != 0) |
|
{ |
|
return mult_div_specials(rhs); |
|
} |
|
return int_adapter<int_type>(value_ / rhs); |
|
} |
|
|
|
// should templatize this to be consistant with op +- |
|
int_adapter operator%(const int_adapter& rhs)const |
|
{ |
|
if(this->is_special() || rhs.is_special()) |
|
{ |
|
if(is_infinity() && rhs.is_infinity()) |
|
{ |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
if(rhs != 0) |
|
{ |
|
return mult_div_specials(rhs); |
|
} |
|
else { // let divide by zero blow itself up |
|
return int_adapter<int_type>(value_ % rhs.value_); |
|
} |
|
} |
|
return int_adapter<int_type>(value_ % rhs.value_); |
|
} |
|
/*! Provided for cases when automatic conversion from |
|
* 'int' to 'int_adapter' causes incorrect results. */ |
|
int_adapter operator%(const int rhs) const |
|
{ |
|
if(is_special() && rhs != 0) |
|
{ |
|
return mult_div_specials(rhs); |
|
} |
|
return int_adapter<int_type>(value_ % rhs); |
|
} |
|
private: |
|
int_type value_; |
|
|
|
//! returns -1, 0, 1, or 2 if 'this' is <, ==, >, or 'nan comparison' rhs |
|
int compare(const int_adapter& rhs)const |
|
{ |
|
if(this->is_special() || rhs.is_special()) |
|
{ |
|
if(this->is_nan() || rhs.is_nan()) { |
|
if(this->is_nan() && rhs.is_nan()) { |
|
return 0; // equal |
|
} |
|
else { |
|
return 2; // nan |
|
} |
|
} |
|
if((is_neg_inf(value_) && !is_neg_inf(rhs.value_)) || |
|
(is_pos_inf(rhs.value_) && !is_pos_inf(value_)) ) |
|
{ |
|
return -1; // less than |
|
} |
|
if((is_pos_inf(value_) && !is_pos_inf(rhs.value_)) || |
|
(is_neg_inf(rhs.value_) && !is_neg_inf(value_)) ) { |
|
return 1; // greater than |
|
} |
|
} |
|
if(value_ < rhs.value_) return -1; |
|
if(value_ > rhs.value_) return 1; |
|
// implied-> if(value_ == rhs.value_) |
|
return 0; |
|
} |
|
/* When multiplying and dividing with at least 1 special value |
|
* very simmilar rules apply. In those cases where the rules |
|
* are different, they are handled in the respective operator |
|
* function. */ |
|
//! Assumes at least 'this' or 'rhs' is a special value |
|
int_adapter mult_div_specials(const int_adapter& rhs)const |
|
{ |
|
int min_value; |
|
// quiets compiler warnings |
|
bool is_signed = std::numeric_limits<int_type>::is_signed; |
|
if(is_signed) { |
|
min_value = 0; |
|
} |
|
else { |
|
min_value = 1;// there is no zero with unsigned |
|
} |
|
if(this->is_nan() || rhs.is_nan()) { |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
if((*this > 0 && rhs > 0) || (*this < min_value && rhs < min_value)) { |
|
return int_adapter<int_type>(pos_infinity()); |
|
} |
|
if((*this > 0 && rhs < min_value) || (*this < min_value && rhs > 0)) { |
|
return int_adapter<int_type>(neg_infinity()); |
|
} |
|
//implied -> if(this->value_ == 0 || rhs.value_ == 0) |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
/* Overloaded function necessary because of special |
|
* situation where int_adapter is instantiated with |
|
* 'unsigned' and func is called with negative int. |
|
* It would produce incorrect results since 'unsigned' |
|
* wraps around when initialized with a negative value */ |
|
//! Assumes 'this' is a special value |
|
int_adapter mult_div_specials(const int& rhs) const |
|
{ |
|
int min_value; |
|
// quiets compiler warnings |
|
bool is_signed = std::numeric_limits<int_type>::is_signed; |
|
if(is_signed) { |
|
min_value = 0; |
|
} |
|
else { |
|
min_value = 1;// there is no zero with unsigned |
|
} |
|
if(this->is_nan()) { |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
if((*this > 0 && rhs > 0) || (*this < min_value && rhs < 0)) { |
|
return int_adapter<int_type>(pos_infinity()); |
|
} |
|
if((*this > 0 && rhs < 0) || (*this < min_value && rhs > 0)) { |
|
return int_adapter<int_type>(neg_infinity()); |
|
} |
|
//implied -> if(this->value_ == 0 || rhs.value_ == 0) |
|
return int_adapter<int_type>(not_a_number()); |
|
} |
|
|
|
}; |
|
|
|
#ifndef BOOST_DATE_TIME_NO_LOCALE |
|
/*! Expected output is either a numeric representation |
|
* or a special values representation.<BR> |
|
* Ex. "12", "+infinity", "not-a-number", etc. */ |
|
//template<class charT = char, class traits = std::traits<charT>, typename int_type> |
|
template<class charT, class traits, typename int_type> |
|
inline |
|
std::basic_ostream<charT, traits>& |
|
operator<<(std::basic_ostream<charT, traits>& os, const int_adapter<int_type>& ia) |
|
{ |
|
if(ia.is_special()) { |
|
// switch copied from date_names_put.hpp |
|
switch(ia.as_special()) |
|
{ |
|
case not_a_date_time: |
|
os << "not-a-number"; |
|
break; |
|
case pos_infin: |
|
os << "+infinity"; |
|
break; |
|
case neg_infin: |
|
os << "-infinity"; |
|
break; |
|
default: |
|
os << ""; |
|
} |
|
} |
|
else { |
|
os << ia.as_number(); |
|
} |
|
return os; |
|
} |
|
#endif |
|
|
|
|
|
} } //namespace date_time |
|
|
|
|
|
|
|
#endif
|
|
|