Is there a way that I can use std::numeric_limits<T>::is_integer
and std::numeric_limits<T>::is_specialized
to change template behavior?
For example can I do this:
template < typename T >
void foo( const T& bar )
{
if( std::numeric_limits< T >::is_integer )
{
isInt( bar );
}
else if( std::numeric_limits< T >::is_specialized )
{
isFloat( bar );
}
else
{
isString( bar );
}
}
The "obvious" answer is that you could use something like std::enable_if
.
For example:
template<typename T>
typename std::enable_if<std::numeric_limits<T>::is_integer, void>::type
foo(const T &bar) { isInt(bar); }
template<typename T>
typename std::enable_if<std::numeric_limits<T>::is_specialized, void>::type
foo(const T &bar) { isFloat(bar); }
The problem with this approach is that this is ambiguous for (as an example) an int
parameter, since numeric_limits<int>::is_specialized == true
.
To resolve this, I would simply use a better trait than numeric_limits
, personally. You can also use boolean conditions to test for the exact condition you want:
template<typename T>
typename std::enable_if<std::numeric_limits<T>::is_specialized && !std::numeric_limits<T>::is_integer, void>::type
foo(const T &bar) { isFloat(bar); }