Erroneous conversion from double to boost::rational<int>

[akrzemi1]

The documentation discusses in detail why conversion from double is not supported, but the following code works fine:

#include <iostream>
#include <boost/rational.hpp>

int main()
{
  double d = 31.82;
  boost::rational<int> r = d;
  std::cout << r << std::endl;
}

With the following result "31/1". It just discards the fractional part. A double is implicitly converted to int and then the implicit constructor from int is used.

Such conversion is really confusing. Make it explicitly declared as deleted.