Extends c++ type traits and implements a few more to boot.
Provides some cross platform type traits above and beyond what is provided
by c++.
Include the following at the top of any translation unit which
requires this library:
@code
#include <ecl/type_traits.hpp>
// The error interfaces
using ecl::numeric_limits;
using ecl::is_integral;
using ecl::is_float;
using ecl::is_signed;
using ecl::is_unsigned;
using ecl::is_byte;
@endcode
You will also need to link to <i>-lecl_type_traits</i>.
This extends c++'s numeric_limits class for fundamental types, providing in addition, static constants
that can be utilised as template arguments (as opposed to c macros or c++ functions in numeric_limits).
For integral types, an example of the extras available:
@code
ecl::uint16 bits = NumericLimits<int>::bits;
ecl::uint16 bytes = NumericLimits<int>::bytes;
int j = NumericLimits<int>::one;
int i = NumericLimits<int>::minimum;
int k = NumericLimits<int>::maximum;
@endcode
An example of some extras for a float type:
@code
ecl::uint16 bits = NumericLimits<float>::bits;
ecl::uint16 bytes = NumericLimits<float>::bytes;
// precision setting is a rough, but useful aid to bounding the accuracy for some math calculations
NumericLimits<float>::Precision p = NumericLimits<float>::dummy_precision();
// note, numeric_limits<float>::min() is the smallest
// positive value, this is the smallest negative value.
float minimum = NumericLimits<float>::minimum;
float maximum = NumericLimits<float>::maximum;
@endcode
Note that it inherits the numeric_limits class, so all the functions therein can also be used.
These are in the upcoming C++0x standard, so are only a temporary feature in the ecl. They
are a subset and work just like boosts type traits. More will be added as needed. The
code snippet below is for runtime code, but they're actually more useful with enable_if
in determining which compile time template specialisations to instantiate.
@code
if ( is_float<double>::value ) {
// take some action
}
@endcode
The current list of type traits include:
- @ref ecl::is_integral "is_integral"
- @ref ecl::is_signed "is_signed"
- @ref ecl::is_unsigned "is_unsigned"
- @ref ecl::is_float "is_float"
- @ref ecl::is_byte "is_byte"
- @ref ecl::is_signed_byte "is_signed_byte"
- @ref ecl::is_unsigned_byte "is_unsigned_byte"
- src/test/numeric_limits.cpp
- src/test/fundamental_types.cpp
- <b>Mar 11</b> : added the is_xxx_byte type traits.
- <b>Feb 11</b> : collected type traits from ecl_config and ecl_mpl.
- <b>Sep 10</b> : @ref ecl::is_byte "is_byte" trait for detection of single byte types added.
- <b>Aug 10</b> : @ref ecl::is_signed "is_signed", @ref ecl::is_unsigned "is_unsigned" trait types added.
- <b>Jul 10</b> : @ref ecl::is_integral "is_integral", @ref ecl::is_float "is_float" trait types added.