At Wed, 25 Aug 2010 22:48:57 -0700,
Ryan McConnehey wrote:
I'm new to the parameter library and started with a simple example to
get my feet wet. The first problem I'm having is with type
restriction. The "name" variable is being restricted to a boolean
type. This doesn't seem to be enforced since I can pass this variable a
value of 15 and get this same value out. Currently my output has "name
= 15" and I expected the output to be "name = 1". Did I not correctly
enforce the type?
Looks like a bug to me. Daniel?
The second problem is with the default value of my variable. I thought
if the variable wasn't used then the third parameter, in the
declaration, is used for instantiation of that variable. I thought that
meant I could do this "m_name(args[_name])". The compiler gives an
error saying the operator[] can't deduce the arguments. What did I not
do that would allow this behavior.
Ditto, looks like a bug. If we don't already have tests for these
cases, we should.
Thank you for your time in helping me out.
Ryan
BOOST_PARAMETER_NAME(name)
struct myclass_impl
{
template <class ArgumentPack>
myclass_impl(ArgumentPack const& args)
: m_name(args[_name | false])
//: m_name(args[_name]) //gives a compile error
{
std::cout << "name = " << m_name << std::endl;
}
private:
int m_name;
};
struct myclass : public myclass_impl
{
BOOST_PARAMETER_CONSTRUCTOR(
myclass, (myclass_impl), tag
, (optional
(name, (bool), bool(false)))) // no semicolon
};
int main(int argc, char* argv[])
{
myclass x(_name = 15);
return 0;
}