[Boost-bugs] [Boost C++ Libraries] #10244: Erroneous conversion from double to boost::rational<int>

Subject: [Boost-bugs] [Boost C++ Libraries] #10244: Erroneous conversion from double to boost::rational<int>
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-07-25 12:58:54

#10244: Erroneous conversion from double to boost::rational<int>
------------------------------+----------------------
 Reporter:  akrzemi1          |      Owner:  turkanis
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  rational
  Version:  Boost 1.55.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+----------------------
 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.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10244>
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