Re: [Boost-users] [Phoenix] Simple if_ issue

2 Jul 2012

      Aaron,

On Mon, Jul 2, 2012 at 1:05 PM, Nathan Crookston
 wrote:
...
On Mon, Jul 2, 2012 at 12:51 PM,   wrote:
<snip code>
...
What do I need to do in the second test to get it to compile? Can I tell
if_ that its return type is not void?
Sadly no -- this was a point of confusion for me too.  The correct way
to do this is with if_else
Sorry to reply twice.  The advice is correct, but the link is wrong
(I'm not sure where if_else is documented. . .).  The following shows
usage:

#include 
#include 
#include <iostream>

namespace px = boost::phoenix;
using px::arg_names::arg1;

int main()
{
  boost::functionstd::string(bool) f = px::if_else(arg1, "true", "false");
  std::cout << f(true) << std::endl;
  std::cout << f(false) << std::endl;
  return 0;
}

HTH,
Nate