base_limits.hpp

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# ifndef CPPAD_CORE_BASE_LIMITS_HPP
# define CPPAD_CORE_BASE_LIMITS_HPP

/* --------------------------------------------------------------------------
CppAD: C++ Algorithmic Differentiation: Copyright (C) 2003-17 Bradley M. Bell

CppAD is distributed under multiple licenses. This distribution is under
the terms of the
                    Eclipse Public License Version 1.0.

A copy of this license is included in the COPYING file of this distribution.
Please visit http://www.coin-or.org/CppAD/ for information on other licenses.
-------------------------------------------------------------------------- */

/*
$begin base_limits$$
$spell
     std
     namespace
     CppAD
$$

$section Base Type Requirements for Numeric Limits$$

$head CppAD::numeric_limits$$
A specialization for
$cref/CppAD::numeric_limits/numeric_limits/$$
must be defined in order to use the type $codei%AD<%Base%>%$$.
CppAD does not use a specialization of
$codei%std::numeric_limits<%Base%>%$$.
Since C++11, using a specialization of
$codei%std::numeric_limits<%Base%>%$$
would require that $icode Base$$ be a literal type.

$head CPPAD_NUMERIC_LIMITS$$
In most cases, this macro can be used to define the specialization where
the numeric limits for the type $icode Base$$
are the same as the standard numeric limits for the type $icode Other$$.
For most $icode Base$$ types,
there is a choice of $icode Other$$,
for which the following preprocessor macro invocation suffices:
$codei%
     namespace CppAD {
          CPPAD_NUMERIC_LIMITS(%Other%, %Base%)
     }
%$$
where the macro is defined by
$srccode%cpp% */
# define CPPAD_NUMERIC_LIMITS(Other, Base) \
template <> class numeric_limits<Base>\
{\
     public:\
     static Base min(void) \
     {    return static_cast<Base>( std::numeric_limits<Other>::min() ); }\
     static Base max(void) \
     {    return static_cast<Base>( std::numeric_limits<Other>::max() ); }\
     static Base epsilon(void) \
     {    return static_cast<Base>( std::numeric_limits<Other>::epsilon() ); }\
     static Base quiet_NaN(void) \
     {    return static_cast<Base>( std::numeric_limits<Other>::quiet_NaN() ); }\
     static const int digits10 = std::numeric_limits<Other>::digits10;\
};
/* %$$
$end
*/

# endif