[Boost-bugs] [Boost C++ Libraries] #13583: quantities can be assigned from cmath sqrt result, but not initialized

Subject: [Boost-bugs] [Boost C++ Libraries] #13583: quantities can be assigned from cmath sqrt result, but not initialized
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2018-05-30 21:33:28

#13583: quantities can be assigned from cmath sqrt result, but not initialized
------------------------------+------------------------------
 Reporter:  edaskel@…         |      Owner:  Matthias Schabel
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  units
  Version:  Boost 1.67.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+------------------------------
 The cmath functions are very helpful in letting me perform math on
 quantities, but I ran across an inconsistency. Code like:

 {{{
     quantity<wavenumber, float> x, y;
     quantity<wavenumber, float> foo = sqrt(x*x + y*y);
 }}}

 fails to compile (with an "error: conversion from..."). The workaround is
 to use an assignment instead:

 {{{
     quantity<wavenumber, float> foo;
     foo = sqrt(x*x + y*y);
 }}}

 It seems odd to have this restriction (and it's certainly undocumented) so
 I suspect it is a bug.

-- 
Ticket URL: <https://svn.boost.org/trac10/ticket/13583>
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