We can have the following and it is valid:
template<std::size_t Size = 10>
fn(){...}
template<typename Size = std::size_t>
fn() {...}
But how to do this?
template<typename Size = std::size_t=10>
fn() {...}
Default template parameter with a default value?
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2 Answers
A template parameter is either a type or a value, it isn't both.
You can do it with two parameters
template<typename Size = std::size_t, Size s = 10>
You could require that your parameter be a specialization of std::integral_constant (or some other type that provides both 'type' and 'value' members:
template<typename Arg = std::integral_constant<size_t, 10>>
struct foo
{ };
but in general I would say the two parameter method is preferable.
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