Re: [Boost-bugs] [Boost C++ Libraries] #10082: implicit cpp_rational(double)

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #10082: implicit cpp_rational(double)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-05-30 18:07:28

#10082: implicit cpp_rational(double)
-------------------------------+----------------------------
  Reporter:  marc.glisse@…     |      Owner:  johnmaddock
      Type:  Bugs              |     Status:  new
 Milestone:  To Be Determined  |  Component:  multiprecision
   Version:  Boost 1.55.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+----------------------------

Comment (by johnmaddock):

 Ugh, I'm a bit conflicted by this: you're quite right that the double
 value is converted exactly, however making this implicit does allow you to
 shoot yourself in the foot, for example:

 {{{
 cpp_rational r(0.1);
 }}}

 Assigns the value 3602879701896397/36028797018963968 to r, which is
 probably not what was intended!  Of course a naive user may just add the
 necessary cast and shoot themselves anyway, but on balance I think I'm
 marginally against making the conversion implicit.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10082#comment:1>
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